CN214130432U - Washing settling tank and multistage washing settling device - Google Patents

Abstract

The utility model belongs to the red mud separation of alumina factory and washing field, concretely relates to washing settling tank and multistage washing subside device are applicable to alumina factory red mud separation and washing process. The method comprises the steps that a Venturi mixer is arranged at the top in a washing and settling tank, the nozzle end of the Venturi mixer is connected with the bottom flow of a previous-stage settling tank, the drainage inlet of the Venturi mixer is connected with the overflow of a next-stage settling tank, the bottom flow of the settling tank is conveyed by a centrifugal pump, the overflow adopts self-flow, the outlet end of the Venturi mixer directly extends into a bell mouth of a feeding pipe, and supernatant in the tank is sucked into the feeding pipe from the bell mouth and completes secondary self-dilution with the bottom flow and the overflow. The foundation of each washing settling tank or the straight cylinder section of the tank body is sequentially heightened so as to achieve the step arrangement of each washing settling tank. The utility model reduces overflow groove and overflow pump by replacing forced mixed feeding with two-stage self-dilution mixed feeding, thereby saving construction investment and operation cost and reducing energy consumption; the venturi mixer improves the mixing effect of the underflow and the overflow.

Description

Washing settling tank and multistage washing settling device

Technical Field

The utility model belongs to the separation of alumina factory red mud and washing field, concretely relates to washing settling tank and multistage washing subside device.

Background

In the process of producing alumina by using a Bayer process, the red mud sodium aluminate mixed ore pulp formed by dissolving bauxite enters a red mud separation and washing process after being diluted, and the process usually adopts a settling tank to realize the liquid-solid separation of the ore pulp and specifically comprises a separation settling tank and a washing settling tank. The separation settling tank is used for separating the sodium aluminate solution and the red mud slurry in the diluted ore pulp, and the red mud slurry enters the washing settling tank to carry out reverse washing for a plurality of times to recover the alumina and the sodium oxide in the red mud slurry.

The incoming materials of the washing settling tank mainly comprise the underflow of the previous-stage settling tank and the overflow of the next-stage settling tank, and the final-stage washing settling tank adopts hot water as the red mud washing liquid. The traditional feeding process is that a feeding main pipe is arranged at the top of a settling tank, the underflow of an upper-stage settling tank is conveyed to the feeding main pipe by an underflow pump, the overflow of a lower-stage settling tank is collected by an overflow tank and then conveyed to the feeding main pipe by an overflow pump, and the underflow and the overflow are mixed in the feeding main pipe and then enter the settling tank. The process has more equipment and large investment; the operation is complicated and the power consumption is large during operation; the underflow pump and the overflow pump are in parallel connection and have mutual influence.

SUMMERY OF THE UTILITY MODEL

The utility model provides a solve above-mentioned problem, provide a novel washing settling basin and arrange the washing that forms by separation settling basin and this kind of novel washing settling basin and subside device. The specific scheme is as follows:

a novel washing and settling tank is structurally shown in figure 2, a feeding main pipe 22 and a Venturi mixer 21 are arranged at the top inside the washing and settling tank, an overflow outlet 25 is arranged at the top of the side wall of the washing and settling tank, and an underflow outlet 24 is arranged at the bottom of the washing and settling tank. The structure of the Venturi mixer is shown in figure 1 and comprises a main feeding hole 11 of the Venturi mixer, a drainage inlet 12 of the Venturi mixer and an outlet 13 of the Venturi mixer. When in use, the main feed inlet 11 of the venturi mixer is communicated with the underflow outlet of the upper-stage separation settling tank or the washing settling tank through a centrifugal pump, and the underflow of the upper-stage settling tank is pumped into the main feed inlet 11 of the venturi mixer through the centrifugal pump; the venturi mixer drainage inlet 12 is communicated with the overflow outlet of the next-stage washing settling tank when in use, and the overflow of the next-stage settling tank enters the venturi mixer drainage inlet 12 in a self-flowing mode.

The outlet of the venturi mixer extends into a feeding main pipe 22, a bell mouth is arranged at one end of the feeding main pipe 22 extending into the outlet 13 of the venturi mixer, and the other end of the feeding main pipe 22 is communicated with a central feeding cylinder 23 inside the washing and settling tank.

The underflow of the previous-stage settling tank enters through a main feed inlet 11 of the Venturi mixer and then is sprayed out from a nozzle 14 in the Venturi mixer, the static pressure energy is reduced, a vacuum zone is formed at the rear side, the overflow of the next-stage settling tank is sucked into a drainage inlet 12 of the Venturi mixer and enters a suction chamber 15, the underflow and the overflow are fully mixed in the Venturi mixer to finish first-stage self dilution, the mixed material flows out through an outlet 13 of the Venturi mixer and enters a feed header pipe 22, meanwhile, the clear liquid in the washing settling tank is also sucked into the feed header pipe 22 through one end of the feed header pipe with a horn mouth and is fully mixed with the mixed material flowing out from the outlet 13 of the Venturi mixer to finish second-stage self dilution; the mixed liquid after the second-stage self-dilution enters the washing and settling tank through the central feeding cylinder 23 of the washing and settling tank, and the feeding can reach the optimal solid content ratio through the first-stage self-dilution and the second-stage self-dilution.

As another aspect of the utility model, still provide a washing settling device who uses above-mentioned washing settling tank, including separation settling tank and n (n is greater than or equal to 2, preferably 4-6) washing settling tanks, the quantity of washing settling tank sets up according to the technological requirement, is called first order, second level, …, nth level washing settling tank respectively, wherein first order to nth-1 level washing settling tank adopt above-mentioned novel washing settling tank. The underflow outlet at the bottom of the separation settling tank is communicated with the main feed inlet of the Venturi mixer of the first-stage washing settling tank through a centrifugal pump, the underflow outlets at the bottoms of all stages of washing settling tanks except the n-1 th and n-th washing settling tanks are communicated with the main feed inlet of the Venturi mixer of the next-stage washing settling tank through a centrifugal pump, the n-th washing settling tank can adopt any washing settling tank in the application or the prior art, and the underflow outlet of the n-1 th washing settling tank is communicated with the n-th washing settling tank through a centrifugal pump.

The overflow outlets at the tops of the second stage and the later stages of the washing and settling tanks are communicated with the drainage inlet of the Venturi mixer of the previous stage of the washing and settling tank through overflow pipelines, and the overflow enters the Venturi mixer of the previous stage of the washing and settling tank in a self-flowing mode, so that an overflow pump and an overflow tank which are commonly used can be omitted.

In order to adapt to the feeding mode and ensure that the overflow can smoothly flow to the Venturi mixer, the arrangement of the settling tank needs to be correspondingly optimized. Each washing settling tank is 0.5-1m higher than the upper washing settling tank, the foundation can be 0.5-1m higher, the straight cylinder section of the tank body can be 0.5-1m higher, the stepped arrangement is realized, a certain liquid level height difference is formed among the settling tanks, and an overflow pipeline at the top of the tank is directly communicated with a drainage inlet of a Venturi mixer in the upper washing settling tank in a sloping direction, so that the liquid level potential energy is fully utilized, and the pipeline arrangement is simplified.

The utility model has the advantages that: the Venturi mixer adopted by the novel washing and settling tank has the advantages of simple structure, mature technology, wide application and easy operation and maintenance, and the two fluids can be mutually converted by means of static pressure energy and dynamic pressure energy so as to achieve a better mixing effect and control the optimal feeding solid content ratio. The overflow of the washing and settling tank of the multi-stage washing and settling device is automatically fed to the previous washing and settling tank by utilizing the gravity, an overflow tank and an overflow pump are omitted, the equipment and civil engineering investment in the construction period is saved, the energy consumption is greatly reduced when the system operates, and the daily inspection and maintenance cost is reduced.

Drawings

FIG. 1 is a schematic diagram of a venturi mixer;

FIG. 2 is a schematic structural view of a washing and settling tank of the present invention;

FIG. 3 is a flow diagram of the underflow and overflow streams of the settling tanks of the wash settling apparatus of example 1;

fig. 4 is a schematic view of the wash settler step arrangement in example 1.

Reference numerals: 11-a main feed inlet of a venturi mixer, 12-a drainage inlet of the venturi mixer, 13-an outlet of the venturi mixer, 14-a nozzle and 15-a suction chamber;

21-a venturi mixer, 22-a feeding main pipe, 23-an intermediate feeding barrel, 24-an underflow outlet and 25-an overflow outlet;

31-1# washing settling tank, 32-2# washing settling tank, 33-3# washing settling tank, 34-4# washing settling tank, 35-separation settling tank and 36-centrifugal pump.

Detailed Description

The invention is further explained below with reference to the drawings and the specific embodiments. The drawings and examples are only for the purpose of illustrating the invention and are not to be construed as limiting the invention in practice.

Example 1:

a red mud separation and washing workshop of an alumina plant is provided with 1 separation settling tank and 4 washing settling tanks, wherein the washing settling tanks are 1#, 2#, 3# and 4# washing settling tanks respectively, and red mud slurry separated by the separation settling tanks is washed for four times. The structure of the No. 1, No. 2 and No. 3 washing settling tank is shown in FIG. 2, the top of the inside of the washing settling tank is provided with a feeding main pipe 22 and a Venturi mixer 21, the top of the side wall of the washing settling tank is provided with an overflow outlet 25, and the bottom of the washing settling tank is provided with an underflow outlet 24. The venturi mixer 21 is constructed as shown in fig. 1.

The venturi mixer outlet 13 extends into the feeding main pipe 22, the feeding main pipe 22 is provided with a bell mouth at the extending end of the venturi mixer outlet 13, and the other end of the feeding main pipe 22 is communicated with the central feeding cylinder 23 in the washing and settling tank.

The venturi mixers in the # 1 washing and settling tank 31, the # 2 washing and settling tank 32 and the # 3 washing and settling tank 33 are the # 1 mixer, the # 2 mixer and the # 3 mixer, respectively. As shown in fig. 3, when the device is used, diluted red mud sodium aluminate mixed ore pulp is injected into a separation settling tank 35, the underflow of the mixed ore pulp is separated red mud slurry, hot water is injected into a No. 4 washing settling tank 34 as red mud washing water, the underflow of the separation settling tank is connected to a main feed inlet of a No. 1 mixer, and the overflow of a No. 2 washing settling tank 32 is connected to a drainage inlet of the No. 1 mixer; the bottom flow of the No. 1 washing settling tank 31 is connected to the main feed inlet of the No. 2 mixer, and the overflow of the No. 3 washing settling tank 33 is connected to the drainage inlet of the No. 2 mixer; the bottom flow of the No. 2 washing and settling tank 32 is connected to the main feed inlet of the No. 3 mixer, and the overflow of the No. 4 washing and settling tank 34 is connected to the drainage inlet of the No. 3 mixer; the underflow of the No. 3 scrubbing-and-settling tank 33 is connected to the No. 4 scrubbing-and-settling tank 34.

All the bottom flows of the settling tanks are pumped into the next settling tank by a centrifugal pump 36, and the overflow of the No. 2, No. 3 and No. 4 washing settling tanks enters the previous settling tank in a self-flowing mode. In the No. 1, No. 2 and No. 3 washing and settling tank with the Venturi mixer 21, the underflow of the previous-stage settling tank and the overflow of the next-stage settling tank form two-stage self-dilution in the Venturi mixer 21 and the feeding header pipe 22, namely, the underflow entering the current washing and settling tank from the previous-stage settling tank is subjected to primary dilution through the overflow of the next-stage washing and settling tank in the Venturi mixer 21, the mixed liquid after the primary dilution is sprayed out from the Venturi mixer outlet 13 and is mixed with the clear liquid entering the current washing and settling tank from the feeding header pipe 22 to form secondary dilution, and then the mixed liquid enters the current washing and settling tank through the central feeding cylinder 23 to be subjected to sedimentation separation, so that the underflow of red mud slurry and the overflow of the clear liquid are formed.

In order to adapt to the feeding mode in this example, as shown in fig. 4, the basic elevations of the separation settling tank 35, the # 1 washing settling tank 31 and the # 2 washing settling tank 32 are ± 0.000m, and the basic elevations of the # 3 washing settling tank 33 and the # 4 washing settling tank 34 are 1.000 m; the height H of the straight cylinder section of the separation settling tank 35, the No. 1 washing settling tank 31 and the No. 3 washing settling tank 33, and the height H +0.5m of the straight cylinder section of the No. 2 washing settling tank 32 and the No. 4 washing settling tank 34. Thus, the height difference of 0.5m is formed between the washing settling tanks, the purpose of step arrangement is achieved, and the settling overflow automatically flows to the upper washing tank by virtue of the height difference.

By adopting the configuration mode of the embodiment, compared with the configuration mode of the traditional process, at least 3 overflow troughs and 6 overflow pumps are saved (considering that each settling tank corresponds to 1 overflow trough and 2 overflow pumps).

Claims (4)

1. A washing and settling tank is characterized in that a feeding main pipe and a Venturi mixer are arranged at the top inside the washing and settling tank, an overflow outlet is arranged at the top of the side wall of the washing and settling tank, and an underflow outlet is arranged at the bottom of the washing and settling tank;

the venturi mixer comprises a main feed inlet of the venturi mixer, a drainage inlet of the venturi mixer and an outlet of the venturi mixer, the outlet of the venturi mixer extends into the feeding main pipe, one end of the feeding main pipe extending into the outlet of the venturi mixer is provided with a bell mouth, and the other end of the feeding main pipe is communicated with the central feeding cylinder inside the washing and settling tank.

2. A multi-stage washing and settling device is characterized by comprising a separation settling tank and n washing and settling tanks, wherein n is more than or equal to 2, and the washing and settling tank from the first stage to the (n-1) th stage adopts the washing and settling tank as claimed in claim 1;

the underflow outlet at the bottom of the separation settling tank is communicated with the main feed inlet of the Venturi mixer of the first-stage washing settling tank through a centrifugal pump, the underflow outlets at the bottoms of all stages of washing settling tanks except the n-1 th-stage washing settling tank and the n-th-stage washing settling tank are communicated with the main feed inlet of the Venturi mixer of the next-stage washing settling tank through a centrifugal pump, and the outflow port of the nth-1 th-stage washing settling tank is communicated with the nth-stage washing settling tank through a centrifugal pump;

and the overflow outlets at the tops of the second stage and the later stages of the washing settling tanks are communicated with the drainage inlet of the Venturi mixer of the previous stage of the washing settling tank through overflow pipelines.

3. The multistage washing and settling device as claimed in claim 2, wherein each stage of washing and settling tank after the first stage is 0.5-1m higher than the foundation of the previous stage of washing and settling tank or 0.5-1m higher than the straight cylinder section of the tank body, so as to form a stepped arrangement, and the overflow pipeline of each stage of washing and settling tank is communicated with the drainage inlet of the venturi mixer of the previous stage of washing and settling tank in a sloping direction.

4. The multistage wash settling device of claim 2 or 3, wherein the number n of wash settling tanks is between 4 and 6.

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