CN108046391B

CN108046391B - Grating type flocculation settling device

Info

Publication number: CN108046391B
Application number: CN201711294353.7A
Authority: CN
Inventors: 林喆; 匡亚莉; 王光辉; 王章国
Original assignee: China University of Mining and Technology CUMT
Current assignee: China University of Mining and Technology CUMT
Priority date: 2017-12-08
Filing date: 2017-12-08
Publication date: 2020-11-06
Anticipated expiration: 2037-12-08
Also published as: CN108046391A

Abstract

The invention discloses a grid type flocculation settling device and a construction method thereof, comprising a settling tank, wherein the center of the settling tank is provided with a flocculation unit, the top of the settling tank is externally connected with an overflow water collecting tank, the flocculation unit comprises a water distribution funnel, a water distribution grid and a flocculation grid, the water distribution funnel, the water distribution grid and the flocculation grid are connected in series from top to bottom, the device utilizes the small-diameter grid bars to strengthen the generation of small vortexes, thereby being beneficial to the collision flocculation of particles, meanwhile, the velocity gradient of the water flow is gradually reduced by continuously adjusting the distance between the grid bars, the crushing of a flocculating constituent can be effectively avoided, the device is adopted for flocculation and sedimentation, can form big flocculating constituent rapidly in the short time to in time subside the separation, effectively improve the flocculation and subside efficiency, utilize this device to replace traditional thickener to carry out the flocculation and subside of coal slime water, reducible equipment area practices thrift investment and working costs.

Description

Grating type flocculation settling device

Technical Field

The invention relates to a sedimentation device, in particular to a grid type flocculation sedimentation device which is suitable for the field of water treatment, and is particularly suitable for coal slime flocculation sedimentation of tail coal of a coal preparation plant.

Background

Flocculation settling is an important step in sewage treatment, and conventional flocculation devices can be divided into hydraulic flocculation reactors and mechanical flocculation reactors, the hydraulic flocculation reactors are energy-saving and easy to maintain and are widely applied, the conventional hydraulic flocculation reactors mainly comprise partition plates, folding plates, grids, grid bars and the like, the reactors usually have uniform velocity gradients, although the velocity gradients can be changed through graded series connection, the change is not timely, and the uncontrollable factors such as floc breakage and the like can be increased due to the cascade flow, so that the flocculation effect is poor, in addition, the flocculation and settling or air flotation stages of the conventional water treatment are separated, so that water flows in a communication pipeline or an open channel, the flocculation time can be increased, and the negative effects such as the breakage of flocs and the like can be caused.

Disclosure of Invention

In order to solve the technical problems, the technical scheme provided by the invention is as follows: the utility model provides a grid formula flocculation and sedimentation device, includes the subsider, the subsider center is provided with the flocculation unit, the external overflow water collecting vat in subsider top, the flocculation unit includes water distribution funnel, water distribution grid, flocculation grid, water distribution funnel, water distribution grid and flocculation grid top-down establish ties.

Furthermore, the flocculation grid is composed of grid bars with circular or polygonal cross sections, the diameter of the grid bars or the diameter (d) of external circles of the grid bars is not more than 10mm, the grid bars are arranged row by row from top to bottom, and the center distance (l) of the grid bars in the 1 st row is₁) D + 5-10 mm, from the 2 nd row, the center distance (l) of the n-th row of grid bars_n) The following method is adopted for determination:

wherein d is the diameter of the grid or the diameter of the circumscribed circle, l₁The center distance of the 1 st row of grid bars, l_n-1Is the center distance u of the grid bars in the previous row₁The average flow velocity of water flowing through the gaps of the first row of grid bars is controlled to be between 0.5m/s and 1m/s by adjusting the flow_nDetermined using the following formula:

in the formula, t_iFor the residence time of the water flowing through the i-row of grate bars, t_i＝l_i/u_i，i＝1～n-1。

Further, the center distance between the nth row of grate bars and the nth-1 row of grate bars is equal to the center distance between the nth-1 row of grate bars.

Furthermore, each row of grid bars is arranged in an axisymmetric manner by taking the center of the flocculation grid as an axis, the grid bars are arranged at the center of the flocculation grid in odd rows, and the grid bars are not arranged at the center of the flocculation grid in even rows, namely, the grid bars in the nth row and the grid bars in the (n-1) th row are arranged in a regular triangle manner at the center axis of the flocculation grid.

Further, the top of the flocculation grid is provided with a second flange, and a second enclosure wall is arranged outside the flocculation grid.

Further, the total height of the flocculation grid does not exceed 2 m.

Furthermore, the water distribution grid is formed by vertically arranging a plurality of parallel grid plates, the spacing distance between the parallel grid plates is 10-20mm, and the height of the water distribution grid is not more than 200 mm.

Furthermore, flanges I are arranged at the upper end and the lower end of the water distribution grid, and a surrounding wall I is further arranged on the outer side of the water distribution grid.

After adopting the structure, the invention has the following advantages: this device utilizes minor diameter grid to strengthen little whirlpool and generates, is favorable to the collision flocculation of granule, simultaneously, through continuous adjustment grid interval, makes the velocity gradient of rivers progressively reduce, can effectively avoid the breakage of flocculating constituent, adopts this device to carry out the flocculation and subsides, can form big flocculating constituent rapidly in the short time to in time sedimentation separation effectively improves the flocculation and subsides efficiency.

The device is used for replacing the traditional thickener to carry out flocculation sedimentation of slime water, so that the floor area of equipment can be reduced, and the investment and the operating cost are saved.

Drawings

FIG. 1 is a schematic structural diagram of a grid type flocculation sedimentation device of the invention.

Fig. 2 is a schematic top view of a grid type flocculation settling device.

FIG. 3 is a schematic diagram of a water distribution grid structure of the grid flocculation sedimentation device.

Fig. 4 is a schematic top view of a water distribution grid of the grid flocculation sedimentation device.

FIG. 5 is a structural schematic diagram of a flocculation grid of the grid type flocculation sedimentation device.

Fig. 6 is a schematic top view of a flocculation grid of the grid type flocculation sedimentation device.

FIG. 7 is a schematic diagram of the arrangement method of the grid bars in the flocculation grid of the grid type flocculation sedimentation device.

As shown in the figure: 1. the system comprises an overflow water collecting tank, 2, a water distribution funnel, 3, a water distribution grid, 301, parallel grid plates, 302, flanges I and 303, surrounding walls I and 4, a flocculation grid, 401, flanges II and 402, surrounding walls II and 403, grid bars, 5 and a settling tank.

Wherein l_nThe center distance of the grid bars in the nth row is shown, wherein n is 1, 2, 3, … ….

Detailed Description

With reference to the attached figures 1-7, the grid type flocculation sedimentation device comprises a sedimentation tank 5, a flocculation unit is arranged in the center of the sedimentation tank 5, the top of the sedimentation tank 5 is externally connected with an overflow water collecting tank 1, the flocculation unit comprises a water distribution funnel 2, a water distribution grid 3 and a flocculation grid 4, and the water distribution funnel 2, the water distribution grid 3 and the flocculation grid 4 are connected in series from top to bottom.

As the preferred embodiment of the embodiment, the flocculation grid 4 is composed of grid bars 403 with circular or polygonal cross sections, the diameter of the grid bars 403 or the diameter (d) of the circumscribed circle thereof is not more than 10mm, the grid bars 403 are arranged row by row from top to bottom, wherein the center distance (l) of the grid bars in the 1 st row is₁) D + 5-10 mm, from the 2 nd row, the center distance (l) of the n-th row of grid bars_n) The following method is adopted for determination:

As described in detail above, in this example, the following results can be calculated by taking d as 5mm, l1 as 10mm, and u0 as 0.625 as m/s, using the above method:

n	l_n(mm)	u_n(mm/s)	total residence time t(s)	Total height h (mm) of grid
					1	10	625	0.008	10
2	10.4	579	0.017	16
					3	10.6	575	0.027	22
4	11	555	0.038	28
					……	……	……	……	……
44	94.9	306	3.586	1317
					45	102.3	305	3.905	1422
46	110.3	304	4.252	1536

The center distance between the nth row of grid bars and the nth-1 row of grid bars is equal to the center distance between the nth-1 row of grid bars.

In the present embodiment, according to the above calculation results, the center distance between the rows of the 1 st and 2 nd rows of the grills is 10mm from the center of the 1 st row of the grills, and the center distance between the rows of the 2 nd and 3 rd rows of the grills is l₂10.4, and so on; each row of grid bars is symmetrically arranged by taking the center of the grid as an axis, the odd rows of grid bars are arranged at the center of the grid, the even rows of grid bars are not arranged at the center of the grid, namely, at the center axis of the grid, the nth row of grid bars and the (n-1) th row of grid bars are arranged in a regular triangle, as shown in the attached figure 7;

the total height of the flocculation grid 4 is not more than 2m, and according to the reference calculation result of the embodiment, 1.5m can be taken, and the retention time of raw water flocculation is about 4 s.

As the preferred embodiment of the embodiment, the top of the flocculation grid 4 is provided with a second flange 401, and the periphery of the flocculation grid 4 is provided with a second surrounding wall 402.

As a preferred embodiment of the embodiment, the water distribution grid 3 is formed by vertically arranging a plurality of parallel grid plates 301, the interval distance between the parallel grid plates 301 is 10-20mm, and the height of the water distribution grid 3 is not more than 200mm, so that raw water from a pipeline can uniformly enter the flocculation grid, but cannot stay for too long time to affect the flocculation effect.

As a preferred embodiment of this embodiment, the upper and lower ends of the water distribution grid 3 are provided with flanges one 302, and the outer side of the water distribution grid 3 is further provided with a surrounding wall one 303.

The present invention and its embodiments have been described above, and the description is not intended to be limiting, and the drawings are only one embodiment of the present invention, and the actual structure is not limited thereto. In summary, those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A grid type flocculation sedimentation device is characterized in that: the device comprises a settling tank, wherein a flocculation unit is arranged in the center of the settling tank, the top of the settling tank is externally connected with an overflow water collecting tank, the flocculation unit comprises a water distribution funnel, a water distribution grid and a flocculation grid, and the water distribution funnel, the water distribution grid and the flocculation grid are connected in series from top to bottom;

the flocculation grid is composed of grid bars with circular or polygonal cross sections, the diameter of the grid bars or the diameter (d) of the circumscribed circle of the grid bars is not more than 10mm, the grid bars are arranged from top to bottom row by row, and the center distance (l) of the grid bars in the 1 st row₁) D + 5-10 mm, from the 2 nd row, the center distance (l) of the n-th row of grid bars_n) The following method is adopted for determination:

2. The grid flocculation settling device of claim 1, wherein: the center distance between the nth row of grid bars and the nth-1 row of grid bars is equal to the center distance between the nth-1 row of grid bars.

3. The grid flocculation settling device of claim 1, wherein: each row of grid bars is arranged by taking the center of the flocculation grid as an axial symmetry, the grid bars are arranged at the center of the flocculation grid in odd rows, and the grid bars are not arranged at the center of the flocculation grid in even rows, namely, the grid bars in the n-th row and the grid bars in the n-1 th row are arranged in a regular triangle at the center shaft of the flocculation grid.

4. The grid flocculation settling device of claim 1, wherein: the top of the flocculation grid is provided with a second flange, and a second enclosure wall is arranged outside the flocculation grid.

5. The grid flocculation settling device of claim 1, wherein: the total height of the flocculation grid is not more than 2 m.

6. The grid flocculation settling device of claim 1, wherein: the water distribution grid is formed by vertically arranging a plurality of parallel grid plates, the spacing distance between the parallel grid plates is 10-20mm, and the height of the water distribution grid is not more than 200 mm.

7. The grid flocculation and sedimentation device of claim 6, wherein: flanges I are arranged at the upper end and the lower end of the water distribution grid, and a surrounding wall I is further arranged on the outer side of the water distribution grid.