CN107537699B - A kind of device for filling in flotation column section - Google Patents
A kind of device for filling in flotation column section Download PDFInfo
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- CN107537699B CN107537699B CN201710817008.0A CN201710817008A CN107537699B CN 107537699 B CN107537699 B CN 107537699B CN 201710817008 A CN201710817008 A CN 201710817008A CN 107537699 B CN107537699 B CN 107537699B
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- sieve plate
- flotation column
- circular hole
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- flotation
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- 238000005188 flotation Methods 0.000 title claims abstract description 72
- 239000011148 porous material Substances 0.000 claims abstract description 13
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 12
- 239000012530 fluid Substances 0.000 abstract description 23
- 230000000694 effects Effects 0.000 abstract description 17
- 230000000903 blocking effect Effects 0.000 abstract description 4
- 238000009826 distribution Methods 0.000 abstract description 3
- 230000004907 flux Effects 0.000 abstract description 3
- 239000010410 layer Substances 0.000 description 29
- 229910052500 inorganic mineral Inorganic materials 0.000 description 8
- 239000011707 mineral Substances 0.000 description 8
- 238000000926 separation method Methods 0.000 description 5
- 238000012856 packing Methods 0.000 description 4
- 230000002411 adverse Effects 0.000 description 3
- 239000006185 dispersion Substances 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000006260 foam Substances 0.000 description 3
- 238000009434 installation Methods 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 3
- 230000003068 static effect Effects 0.000 description 3
- 239000010419 fine particle Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000005457 optimization Methods 0.000 description 2
- 230000001174 ascending effect Effects 0.000 description 1
- 230000033558 biomineral tissue development Effects 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 230000002459 sustained effect Effects 0.000 description 1
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Abstract
The invention discloses the device for filling in a kind of flotation column section, including the sieve plate layer to match in flotation column with flotation column dimension is arranged in, the sieve plate layer includes one layer of uniform sieve plate that flotation column top is arranged in and one to three layer of non-homogeneous sieve plate that flotation column lower part is arranged in, and is supported between two layers adjacent of sieve plate by water conservancy diversion round tube;The circular hole of the radially arranged different pore size of non-homogeneous sieve plate, wherein, the circular hole aperture of central area A and sieve plate fringe region B are smaller, and region C circular hole aperture between the two is larger, the circular hole aperture in a-quadrant to the region C becomes larger, and the circular hole aperture in the region C to B area gradually becomes smaller;The circular hole of radially even arrangement same apertures on uniform sieve plate.The present invention is arranged according to the rule of fluid, therefore the distribution of bubble can be made more uniform, and rectification effect more preferably, to effectively improve separating effect, and increases the dischargeable capacity in flotation column, increases ore pulp flux, prevent from blocking.
Description
Technical field
The present invention relates to a kind of flotation columns, and in particular to the device for filling in a kind of flotation column section belongs to ore dressing and sets
Standby technical field.
Background technique
Cyclonic-static fine-bubble flotation column is a kind of novel pillar screening installation with China's independent intellectual property right, special
Some steps optimization separating structure makes COLUMN TECHNOLOGY succeed in terms of China's sorting mineral application, is particularly suitable for fine
The flotation of grain mineral.Step optimization sorting includes column flotation, rotational flow sorting, pipe stream mineralising three parts, respectively corresponds flotation column
Column flotation section, eddy flow section and pipe stream section.Equipment body is cylindrical, and column flotation section and rotational flow sorting section connect at up-down structure is straight-through
Connect, pipe stream mineralization device is arranged in outside equipment cylinder, tangentially connected with rotational flow sorting section, when ore pulp by the tangential high speed of pipe stream section into
When entering eddy flow section, high-intensitive centrifugal force field will be generated, thus strengthen the collision between fine-particle minerals and bubble, it is final to realize
Improve the purpose of flotation recovery rate.For the column flotation section on top, it is desirable that in static fluid environment, collide mine using adverse current
Change floating principle, realize that the mineralising of fine-particle minerals traps and plays selected centrifugation simultaneously, therefore, in order to guarantee that adverse current is touched
Hitting mineralising can smoothly carry out, and then improve the efficiency of separation, need to present plunger stream mode in column flotation section.But due to column
Flotation section goes to upper and lower structure with eddy flow section and connect, so strong cyclone field can be moved up and be spread to column flotation section, this certainly will be
Column flotation section generates the fluid environment that strong eddy flow, maelstrom etc. are unfavorable for static separation, and then can deteriorate adverse current collision mineralising
Effect and concentrate quality.
Contradiction between separating to solve this strong cyclone field with the static of column flotation, the prior art are used in eddy flow
The technology that sorting section is filled, filling medium mainly include yarn quality index and two kinds of filling packing.Filling packing is filled with sieve plate
It fills out compared to more efficient, but its ore pulp handling capacity is small, is not only easy blocking, but also cost is high, installation maintenance is difficult;And
Sieve plate has many advantages, such as that structure is simple, low cost, but rectification effect is poor, and filling effect is limited.
There are also the methods of a kind of comprehensive yarn quality index and filling packing, i.e., use filling packing in the selected area of column flotation section,
Yarn quality index is used in rotational flow sorting area, the material space that enters between the two does not fill, and sieve plate is conducive to stable foam layer, inhibits machine
Tool is carried secretly and is mixed, and filler is conducive to improve the recycling ability and sorting selectivity of column flotation section.But it is filled in this mixing
In filling out, the hole on sieve plate is uniformly arranged, i.e., aperture is identical with pitch of holes, and the bubble disperse in column flotation section is in uneven
State, single layer sieve plate rectification effect is limited, therefore six layers or more of sieve plate would generally be arranged, and can reduce the effective of flotation column in this way
Volume, and it is at high cost, later maintenance is difficult.
Summary of the invention
To solve the above problems, the present invention provides the device for filling in a kind of flotation column section, flotation can be effectively improved
The uneven disperse situation of bubble, filling effect is good, improves the efficiency of separation of flotation column, and the device ore pulp flux is big, is not easy
Blocking, structure is simple, and cost is relatively low, easy to maintain.
Device for filling in a kind of flotation column section of the present invention, including be arranged in flotation column and flotation column dimension phase
The sieve plate layer matched, the sieve plate layer include that one layer of uniform sieve plate on flotation column top is arranged in and is arranged in the one of flotation column lower part
Straight three layers of non-homogeneous sieve plate is supported by water conservancy diversion round tube between two layers adjacent of sieve plate;The non-homogeneous sieve plate is radially arranged
The circular hole of different pore size, wherein the circular hole aperture of central area A and sieve plate fringe region B are less than the circle of region C between the two
The circular hole aperture in hole aperture, a-quadrant to the region C becomes larger, and the circular hole aperture in the region C to B area gradually becomes smaller;Uniform sieve plate
The circular hole of upper radially even arrangement same apertures.
After entering pressurized circulation pump by the recirculated water that flotation column cyclonic separation section is discharged, high-speed jet is converted by nozzle
And bulk gas is introduced, the bubble of high degree of dispersion is then formed by bubble generator, bubble population is under the action of jet stream and eddy flow
It is moved around column central axis spiral, apparent axial eddy is formed, according to fluid mechanics principle it is found that in post jamb face and axis
The axial velocity of heart regional fluid is high, and region axial velocity between the two is low, the aperture on sieve plate can make fluid by
Certain resistance is to generate pressure drop, and aperture is smaller, and pressure drop is bigger, and aperture is bigger, and pressure drop is smaller;Therefore, in order to make bubble point
Dissipate more uniform, to improve sorting mineral efficiency, the uneven sieve plate that the present invention is arranged can be according to fluid in flotation column point
The circular hole of the different setting different pore sizes of axial velocity in selections;Aperture on sieve plate is in addition to that can make fluid be generated by resistance
Outside the effect of pressure drop, also have the function of eliminating eddy flow, according to fluid mechanics principle it is found that fluid is angled into flotation
When column, the wherein tangential velocity highest in side wall region, and the tangential velocity of central area is minimum, is arranged on uneven sieve plate different
Aperture " steering " effect for being subject to fluid it is different, therefore when tangential velocity is bigger, arrangement aperture answer it is smaller, conversely, aperture
Ying Yue great;In column flotation section short transverse, closer to lower section, eddy flow section bubble disperse degree of irregularity is more serious, therefore under
Portion arranges that one to three layer of non-homogeneous sieve plate is used to improve the uneven disperse situation of flotation bubble, and one layer of uniformly sieve is arranged in top
Plate is used for stable foam layer.
Further, flotation column diameter is D, and the region C is the annular region concentric with the sieve plate center of circle, annular region
Interior circular diameter is 0.2~0.3D, and outside diameter is 0.6~0.8D.
The problems such as comprehensively considering rectification effect, the structural strength of sieve plate, aperture cannot be too small, can not be excessive, therefore non-
Aperture is 5-15mm, pitch of holes 1.5-3mm, plate thickness 5-10mm on uniform sieve plate, and pore size is according to above-mentioned rule
Restrain subregion setting.
Further, aperture is 5-15mm, pitch of holes 1.5-3mm, plate thickness 5-10mm on uniform sieve plate.
Further, spacing is 0.5~1.5D between adjacent two layers sieve plate.
Further, water conservancy diversion round tube there are four setting between adjacent two layers sieve plate, is uniformly located at the edge of sieve plate;The water conservancy diversion
Diameter d≤0.1D of round tube.Diversion pipe is used to support two layers adjacent of sieve plate, and its diameter is smaller, therefore it is limited to take up space,
The dischargeable capacity of flotation column is not influenced.
Traditional uniform sieve plate filling is to plan the flowing of ore pulp pair in cylinder using sieve pore regular on uniform sieve plate mostly
Property, make fluid from disorder to order, and the tilt angle of bubble ascending path is varied multiple times by different height sieve pore, extends gas
Bubble rises distance, promotes mineral grain mineralising;And the present invention overcomes previous technology prejudice, using on non-homogeneous sieve plate not
With the sieve pore and combination fluid rule of pore size, make the more uniform, orderly of the bubble disperse of fluid, and not by rule
Sieve pore is planned, and the tilt angle of bubble can be varied multiple times on same layer sieve plate, reduces the merger of bubble, is promoted
Collision adherency between mineral grain and bubble, to substantially increase flotation efficiency;Device for filling provided by the invention, and it is normal
The uniform filling mediums of structures such as rule sieve plate, honeycomb duct are compared, and design combines the fluid dynamics in flotation column, according to stream
The rule setting of body, therefore the distribution of bubble can be made more uniform, rectification effect is more preferably;And due to uneven sieve plate compared to
Uniform sieve plate can significantly more efficient elimination eddy flow, therefore the arrangement number of plies of sieve plate can be reduced, to increase in flotation column
Dischargeable capacity increases ore pulp flux, prevents from blocking, while also reducing installation and maintenance workload, reduces production cost.
Detailed description of the invention
Fig. 1 is the structural diagram of the present invention;
Fig. 2 is the top view of non-homogeneous sieve plate in Fig. 1;
Fig. 3 is the top view of uniform sieve plate in Fig. 1;
Fig. 4 is motion pattern in unfilled flotation column;
Axial velocity profile curve graph when Fig. 5 is unfilled;
Tangential velocity scatter chart when Fig. 6 is unfilled;
Fig. 7 is that filling front and back velocity standard deviation compares table;
In figure: 1, flotation column, 2, uniform sieve plate, 3, non-homogeneous sieve plate, 4, water conservancy diversion round tube.
Specific embodiment
The present invention will be further explained below with reference to the attached drawings.
As shown in Figures 1 to 3, the device for filling in a kind of flotation column section, including be arranged in flotation column 1 and flotation column
The sieve plate layer that size matches, the sieve plate layer include that one layer of uniform sieve plate 2 on flotation column top is arranged in and is arranged in flotation
The non-homogeneous sieve plate 3 of one to three layer of column lower part is supported by water conservancy diversion round tube 4 between two layers adjacent of sieve plate;The non-homogeneous sieve
The circular hole of the radially arranged different pore size of plate 3, wherein the circular hole aperture of central area A and sieve plate fringe region B are less than the two
Between region C circular hole aperture, the circular hole aperture of a-quadrant to the region C becomes larger, and the circular hole aperture in the region C to B area is gradually
Become smaller;The circular hole of radially even arrangement same apertures on uniform sieve plate 2.
Two layers of non-homogeneous sieve plate, one layer of uniform sieve plate is arranged in embodiment in figure.
After entering pressurized circulation pump by the recirculated water that flotation column cyclonic separation section is discharged, high-speed jet is converted by nozzle
And bulk gas is introduced, then there is bubble generator to form the bubble of high degree of dispersion, as shown in figure 4, bubble population is in jet stream and rotation
It is moved under the action of stream around column central axis spiral, apparent axial eddy is formed, according to fluid mechanics principle it is found that such as
Shown in Fig. 5, in the axial velocity of post jamb face and central core region fluid height, and region axial velocity between the two is low, on sieve plate
Aperture can make fluid by certain resistance to generating pressure drop, aperture is smaller, and pressure drop is bigger, and aperture is bigger, and pressure drop is got over
It is small;Therefore in order to keep bubble dispersion more uniform, to improve sorting mineral efficiency, the uneven sieve plate that the present invention is arranged can be with
According to the circular hole of fluid different setting different pore sizes of axial velocity in flotation column section;Aperture on sieve plate is in addition to can be with
Make fluid receive resistance to generate outside the effect of pressure drop, also have the function of eliminating eddy flow, according to fluid mechanics principle it is found that as schemed
Shown in 6, when fluid is angled into flotation column, the wherein tangential velocity highest in side wall region, and central area is tangential
Speed is minimum, it is different that " steering " effect that different apertures is subject to fluid is arranged on uneven sieve plate, therefore tangential velocity is got over
When big, arrangement aperture answer it is smaller, conversely, aperture Ying Yue great;In column flotation section short transverse, closer to lower section eddy flow section bubble
Disperse degree of irregularity is more serious, therefore in one to three layer of lower disposed non-homogeneous sieve plate for improving the uneven of flotation bubble
One layer of uniform sieve plate is arranged in disperse situation, top, is used for stable foam layer.
Further, 1 diameter of flotation column is D, and the region C is the annular region concentric with the sieve plate center of circle, annular region
Interior circular diameter be 0.2~0.3D, outside diameter be 0.6~0.8D.
The problems such as comprehensively considering rectification effect, the structural strength of sieve plate, aperture cannot be too small, can not be excessive, therefore non-
Aperture is 5-15mm, pitch of holes 1.5-3mm, plate thickness 5-10mm on uniform sieve plate 3, and pore size is according to above-mentioned rule
Restrain subregion setting.
Further, aperture is 5-15mm, pitch of holes 1.5-3mm, plate thickness 5-10mm on uniform sieve plate 2.
Further, 1 diameter of flotation column is D, and spacing is 0.5~1.5D between adjacent two layers sieve plate.
Further, water conservancy diversion round tube 4 there are four setting between adjacent two layers sieve plate, is uniformly located at the edge of sieve plate;It is described to lead
Flow diameter d≤0.1D of round tube 4.Diversion pipe is used to support two layers adjacent of sieve plate, and its diameter is smaller, therefore takes up space and have
Limit, does not influence the dischargeable capacity of flotation column.
In order to which the effect to apparatus of the present invention is verified, using 17.0 software of Fluent, Numerical Experiment pair is utilized
One layer of uniform sieve plate of arrangement and one layer of non-homogeneous yarn quality index effect are compared, wherein the circular hole aperture on uniform sieve plate is
10mm, the circular hole aperture on non-homogeneous sieve plate are 9~12mm, and stream-static microbubble floatation column column diameter is 190mm, a height of
1400mm。
After numerical simulation, chooses the speed in column flotation section in sustained height plane and compare, comparing result is such as
Shown in Fig. 7.As seen from Figure 7, after non-homogeneous yarn quality index, the standard deviation of axial velocity and tangential velocity is below uniform
Half when filling, it is seen that when using non-homogeneous yarn quality index, speed field distribution is more preferably uniform, and effect is substantially better than uniform sieve plate
Filling, to keep bubble disperse more uniform.
Claims (6)
1. the device for filling in a kind of flotation column section matches in flotation column (1) with flotation column dimension including setting
Sieve plate layer, which is characterized in that the sieve plate layer includes that one layer of uniform sieve plate (3) on flotation column top is arranged in and is arranged in flotation
The non-homogeneous sieve plate of one to three layer of column lower part (2) is supported by water conservancy diversion round tube (4) between two layers adjacent of sieve plate;It is described non-equal
The circular hole of the radially arranged different pore size of even sieve plate (2), wherein the circular hole aperture of central area A and sieve plate fringe region B are less than
The circular hole aperture in the circular hole aperture of region C between the two, a-quadrant to the region C becomes larger, the circular hole hole in the region C to B area
Diameter gradually becomes smaller;The circular hole of radially even arrangement same apertures on uniform sieve plate (3).
2. the device for filling in flotation column section as described in claim 1, which is characterized in that flotation column (1) diameter is D,
The region C is the annular region concentric with the sieve plate center of circle, and the interior circular diameter of annular region is 0.2~0.3D, and outside diameter is
0.6~0.8D.
3. the device for filling in flotation column section as claimed in claim 2, which is characterized in that hole on non-homogeneous sieve plate (2)
Diameter is 5~15mm, and pitch of holes is 1.5~3mm, and plate thickness is 5~10mm.
4. the device for filling in flotation column section as claimed in claim 3, which is characterized in that aperture on uniform sieve plate (3)
For 5~15mm, pitch of holes is 1.5~3mm, and plate thickness is 5~10mm.
5. the device for filling in flotation column section as claimed in claim 4, which is characterized in that between adjacent two layers sieve plate
Away from for 0.5~1.5D.
6. the device for filling in flotation column section according to any one of claims 1 to 5, which is characterized in that phase
There are four setting between adjacent two layers of sieve plate water conservancy diversion round tube (4), it is uniformly located at the edge of sieve plate;The diameter d of the water conservancy diversion round tube (4)≤
0.1D。
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CN201710817008.0A CN107537699B (en) | 2017-09-12 | 2017-09-12 | A kind of device for filling in flotation column section |
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CN201710817008.0A CN107537699B (en) | 2017-09-12 | 2017-09-12 | A kind of device for filling in flotation column section |
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CN109290069B (en) * | 2018-09-25 | 2021-01-05 | 北矿机电科技有限责任公司 | Device that foam layer intensity increases |
CN109453903B (en) * | 2018-11-23 | 2019-12-31 | 中南大学 | Filling type flotation column |
Citations (4)
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---|---|---|---|---|
CN2431047Y (en) * | 2000-07-07 | 2001-05-23 | 中国矿业大学(北京校区) | Bidirectionally inflating jet flotation column |
CN205323989U (en) * | 2016-01-09 | 2016-06-22 | 山东莱芜煤矿机械有限公司 | Small -size inflatable flotation column testing machine |
CN106076660A (en) * | 2016-06-03 | 2016-11-09 | 武汉工程大学 | A kind of flotation column equipment and method for separating |
BR202015024339U2 (en) * | 2015-09-22 | 2017-03-28 | Pontual Consultoria Empresarial Pesquisa E Desenvolvimento Mineral Ltda Me | double aeration flotation column |
-
2017
- 2017-09-12 CN CN201710817008.0A patent/CN107537699B/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN2431047Y (en) * | 2000-07-07 | 2001-05-23 | 中国矿业大学(北京校区) | Bidirectionally inflating jet flotation column |
BR202015024339U2 (en) * | 2015-09-22 | 2017-03-28 | Pontual Consultoria Empresarial Pesquisa E Desenvolvimento Mineral Ltda Me | double aeration flotation column |
CN205323989U (en) * | 2016-01-09 | 2016-06-22 | 山东莱芜煤矿机械有限公司 | Small -size inflatable flotation column testing machine |
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Non-Patent Citations (1)
Title |
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浮选柱充填及筛板作用分析;路阳 等;《煤炭技术》;20100710;第29卷(第7期);第94-96页 * |
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