Comprehensive treatment device for phosphorus pentoxide tail washing wastewater

Abstract

The utility model discloses a comprehensive treatment device for phosphorus pentoxide tail washing wastewater, which comprises a primary treatment pond and a secondary treatment pond, a wastewater delivery pipe and a first communicating pipe are arranged at the upper part of the primary treatment pond, an alkali adding pipeline is arranged above the primary treatment pond, and a first blow-off pipe is arranged at the bottom of the primary treatment pond; a mixer is installed at the end of the first communicating pipe, a first dosing pipeline, a second dosing pipeline and a stirring mechanism are sequentially arranged in the mixer in the water flow direction, an inner precipitation tank is arranged at the bottom in the secondary treatment pond, and second blow-off pipes are arranged at the positions, on the inner side and the outer side of the inner precipitation tank, of the bottom of the secondary treatment pond; the top of the mixer is provided with a second communicating pipe extending below the inner precipitation tank, the upper part of the outer side of the secondary treatment tank is provided with an overflow tank, and the lower part of the overflow tank is provided with a water outlet pipe. According to the device, on one hand, the wastewater treatment process is shortened, on the other hand, the treatment cost is reduced, and the wastewater purification treatment effect is good.

Description

TECHNICAL FIELD

[0001] The utility model belongs to phosphorus chemical production technical field, concretely relates to a comprehensive treatment device for phosphorus pentoxide tail washing wastewater. BACKGROUND

[0002] Phosphorus pentoxide is a raw material and reagent commonly used in chemical industry, and is widely used in various fields. High-quality phosphorus pentoxide can also be used to produce high-purity phosphoric acid of various concentrations, especially polyphosphoric acid. Currently, the preparation of phosphorus pentoxide in industry generally adopts the oxidation combustion method: taking yellow phosphorus as the raw material, the yellow phosphorus is heated and melted and then added to a combustion furnace. Dry air is introduced into the combustion furnace to react with the yellow phosphorus for combustion, generating phosphorus pentoxide flue gas. The phosphorus pentoxide flue gas is then cooled and settled to produce finished phosphorus pentoxide. The produced phosphorus pentoxide product is in the form of particles. In order to meet the use requirements of customers, the granular phosphorus pentoxide needs to be made into powder. In the above production system, a large amount of tail washing wastewater is generated during the spray condensation of phosphorus pentoxide production tail gas. These tail washing wastewater usually contains a high phosphorus content and other impurities. If it is directly discharged without treatment, it will pollute the environment. In the existing technology, the phosphoric acid tail washing wastewater is mainly treated by evaporation concentration or sedimentation purification. Although evaporation concentration can directly obtain phosphoric acid products, the phosphoric acid concentration of the tail washing wastewater is very low. The evaporation concentration process is complex and requires a large amount of energy consumption. The treatment cost is much higher than the sales cost of the products, and it is not an ideal treatment method. Therefore, it is an objective need to develop a comprehensive treatment device for phosphorus pentoxide tail washing wastewater, which has a simple treatment process, low treatment cost, and good treatment effect. SUMMARY

[0003] The utility model aims at providing a comprehensive treatment device for phosphorus pentoxide tail washing wastewater, which has a simple treatment process, low treatment cost, and good treatment effect.

[0004] The utility model aims at providing a comprehensive treatment device for phosphorus pentoxide tail washing wastewater, which has a simple treatment process, low treatment cost, and good treatment effect. The utility model discloses a first treatment pool and second treatment pool, one side of the upper portion of first treatment pool is provided with wastewater delivery pipe, other side is provided with first communication pipe, first treatment pool top is provided with the alkali adding pipe line of extension to first treatment pool, the bottom of first treatment pool is provided with first blowdown pipe, the end of first communication pipe is installed with the mixer, the mixer is provided with first dosing pipe, second dosing pipe and stirring mechanism in turn along the water flow direction in, the bottom in second treatment pool is provided with inner sedimentation tank, the top of inner sedimentation tank is lower than the top of second treatment pool, the bottom of second treatment pool is provided with second blowdown pipe on the inner side and the outer side of inner sedimentation tank, is provided with blowdown valve on first blowdown pipe and second blowdown pipe, the top of mixer is provided with the second communication pipe of extension to the below of inner sedimentation tank, the upper portion of second treatment pool outer side is provided with overflow pool, the lower portion of overflow pool is provided with outlet pipe.

[0005] Compared with the traditional treatment technology, the device has the advantages that: first, the device utilizes the principle of acid-base neutralization, adds alkaline reagent into the first treatment tank through the alkali adding pipeline, the alkaline reagent reacts with the wastewater to generate phosphate precipitate, the phosphate precipitate is precipitated in the first treatment tank and then discharged through the first blowdown pipe, so that the first-stage precipitation treatment of the wastewater is realized; second, the wastewater treated by the first-stage precipitation treatment enters the mixer, flocculants are added into the mixer through the first dosing pipe and the second dosing pipe, the flocculants and the wastewater are mixed and stirred by the stirring mechanism, so that the flocculation reaction of the wastewater and the flocculants is fully carried out, the wastewater after the flocculation reaction first enters the inner sedimentation tank, then overflows the outer side of the inner sedimentation tank, and then is precipitated again, so that the flocculation particles of the wastewater are precipitated, the purpose of purifying the wastewater is achieved, the wastewater treated by the second-stage treatment tank is reserved in the overflow tank, can be discharged through the water outlet pipe for recycling, and the flocculation particles precipitated at the bottom of the second treatment tank are discharged through the second blowdown pipe. The device adopts the structure that the first treatment tank, the mixer and the second treatment tank cooperate with each other, on the one hand, the process of the wastewater treatment is shortened, the process of the wastewater treatment is simplified, on the other hand, the effect of the wastewater treatment is improved, the phosphoric acid in the wastewater can be removed well after the two-stage precipitation and purification treatment, the recycling of the wastewater is realized, not only the treatment cost is effectively reduced, but also the phosphoric acid content in the treated wastewater is low, the effect of the wastewater purification treatment is good, and the device is easy to popularize and use. BRIEF DESCRIPTION OF DRAWINGS

[0006] Figure 1 It is a whole structure schematic view of the utility model;

[0007] In the drawing: 1-first treatment tank, 11-wastewater conveying pipe, 12-first communication pipe, 13-first blowdown pipe, 14-reagent storage tank, 15-feeding pipe, 16-rotary joint, 17-driving motor, 18-driving gear, 19-driven gear, 110-stirring rod, 111-seepage tank, 2-second treatment tank, 21-inner sedimentation tank, 22-second blowdown pipe, 23-filter screen, 24-buffering cone cap, 25-baffle, 26-inclined plate filter layer, 27-activated carbon filter layer, 3-mixer, 31-stirring mechanism, 32-second communication pipe, 33-flocculant storage tank, 34-dosing pipe, 4-overflow tank, 41-water outlet pipe. DETAILED DESCRIPTION

[0008] The utility model will be further described below in combination with the drawings, but in any way to the utility model is limited, based on the utility model teaching made any change or improvement, all belong to the protection scope of the utility model.

[0009] As Figure 1The utility model discloses a wastewater treatment device, including primary treatment pool 1 and secondary treatment pool 2, one side of primary treatment pool 1 upper portion is provided with waste water delivery pipe 11, and the other side is provided with first communicating pipe 12, and the top of primary treatment pool 1 is provided with the alkali adding pipeline extending to primary treatment pool 1, and the bottom of primary treatment pool 1 is provided with first blow-off pipe 13, the end of first communicating pipe 12 is installed with mixer 3, the first dosing pipeline, second dosing pipeline and stirring mechanism 31 are sequentially provided in mixer 3 along the water flow direction, the bottom in secondary treatment pool 2 is provided with inner sedimentation tank 21, and the top of inner sedimentation tank 21 is lower than the top of secondary treatment pool 2, and the bottom of secondary treatment pool 2 is provided with second blow-off pipe 22 on the inner side and the outer side of inner sedimentation tank 21, and the blow-off valve is provided on first blow-off pipe 13 and second blow-off pipe 22, and the top of mixer 3 is provided with the second communicating pipe 32 extending to the below of inner sedimentation tank 21, and the upper portion of the outer side of secondary treatment pool 2 is provided with overflow pool 4, and the lower part of overflow pool 4 is provided with water outlet pipe 41.

[0010] The working process of the device is: in use, the wastewater enters the first-stage treatment tank 1 through the wastewater conveying pipe 11, and in the process of entering the first-stage treatment tank 1, the alkaline agent is added into the first-stage treatment tank 1 through the alkali pipe, which can be lime, NaOH, etc. After the acid-base neutralization reaction of the alkaline agent and the wastewater in the first-stage treatment tank 1, phosphate precipitate is generated, which is discharged through the first blowdown pipe 13 after precipitation in the first-stage treatment tank 1, thereby realizing the first-stage precipitation treatment of the wastewater. The wastewater after the first-stage precipitation treatment enters the mixer 3, at which time the flocculant is added into the mixer 3 through the first dosing pipe and the second dosing pipe, which can be PAC and PAM in the prior art. The flocculant can promote the aggregation of fine phosphate particles in the wastewater and improve the precipitation efficiency. The flocculant and the wastewater are mixed and stirred by the stirring mechanism 31, so that the flocculation reaction of the flocculant and the wastewater is fully carried out. After the flocculation reaction, the wastewater first enters the inner sedimentation tank 21, and after the sedimentation of the inner sedimentation tank 21, the fine particles are precipitated at the bottom of the inner sedimentation tank 21. The overflow tank of the wastewater is outside the inner sedimentation tank 21, and after the second precipitation, the flocculation particles of the wastewater can be separated and precipitated again to achieve the purpose of wastewater purification. The wastewater treated by the second-stage treatment tank 2 is precipitated and reserved in the overflow tank 4, which can be discharged through the outlet pipe 41 for recycling. The flocculation particles precipitated at the bottom of the second-stage treatment tank 2 are discharged from the second blowdown pipe 22. The device adopts the structure of the first-stage treatment tank 1, the mixer 3 and the second-stage treatment tank 2 cooperating with each other, which on the one hand shortens the process of wastewater treatment and simplifies the process of wastewater treatment, and on the other hand improves the effect of wastewater treatment. After two-stage precipitation and purification treatment, the phosphate in the wastewater can be removed well, the wastewater can be recycled, the treatment cost is effectively reduced, the phosphate content in the treated wastewater is low, and the effect of wastewater purification treatment is good.

[0011] Further, the alkali adding pipeline comprises an alkali medicament storage tank 14 and a medicament feeding pipe 15, the medicament feeding pipe 15 extends to the lower part in the primary treatment tank 1, the lower end of the medicament feeding pipe 15 is provided with a sealing plate, a plurality of distribution holes are uniformly arranged at the lower part of the medicament feeding pipe 15 in the primary treatment tank 1, a first flow meter and a first control valve are sequentially arranged on the medicament feeding pipe 15 close to the alkali medicament storage tank 14, the first flow meter and the first control valve facilitate the control of the flow of the alkali medicament, improve the reaction effect of the alkali medicament and the wastewater, and in use, the first control valve is opened, the alkali medicament stored in the alkali medicament storage tank enters the medicament feeding pipe, and then is distributed in the primary treatment tank through the plurality of distribution holes, so that the alkali medicament and the wastewater are fully mixed, and the effect of acid-base neutralization is improved, and preferably, in order to improve the mixing effect of the alkali medicament and the wastewater, the medicament feeding pipe 15 comprises a first pipe section and a second pipe section, the first pipe section and the second pipe section are connected through a rotary joint 16, a driving motor 17 is mounted on the top of the primary treatment tank 1 through a support, the driving motor 17 is a structure used in the prior art, and a finished product can be directly purchased according to the power size, a driving gear 18 is mounted on the output shaft of the driving motor 17, a driven gear 19 is mounted on the second pipe section and meshes with the driving gear 18, and a plurality of stirring rods 110 are mounted on the lower part of the second pipe section, in use, the driving motor is started, the driving motor drives the driving gear to rotate, the driving gear drives the driven gear to rotate, the driven gear drives the second pipe section to rotate, the alkali medicament entering the second pipe section is rotated into the primary treatment tank in the process of rotation of the second pipe section, so that the alkali medicament and the wastewater are fully mixed, and in the process, the rotation of the second pipe section also drives the stirring rods to rotate, the rotation of the stirring rods can stir and mix the wastewater and the alkali medicament, and the mixing effect is further improved.

[0012] Further, the first communication pipe 12 is located above the wastewater conveying pipe 11, the outlet of the wastewater conveying pipe 11 faces the bottom of the primary treatment tank 1, and a water seepage tank 111 is arranged in the primary treatment tank 1 at the inlet of the first communication pipe 12, a plurality of water seepage holes are uniformly arranged on the bottom of the water seepage tank 111, the wastewater and the alkali medicament are mixed to produce phosphate precipitate, the water seepage tank 111 has the function of filtering the precipitate, the phosphate precipitate is intercepted by the water seepage tank 111 and is deposited on the bottom of the primary treatment tank 1, the wastewater enters the water seepage tank 111 through the water seepage holes, and finally is discharged through the first communication pipe 12.

[0013] Further, in order to facilitate the addition of the flocculant, the first medicament adding pipeline and the second medicament adding pipeline have the same structure and both comprise a flocculant storage tank 33 and a medicament adding pipe 34, the medicament adding pipe 34 is provided with a second flow meter and a second control valve, the second flow meter and the second control valve are used to facilitate the control of the addition amount of the flocculant, and the stirring mechanism 31 used in the mixer 3 has the structure used in the prior art,

[0014] Further, in order to improve the sedimentation effect of the secondary treatment tank 2, the inner space of the inner sedimentation tank 21 gradually increases from top to bottom, a filter screen 23 is arranged at the lower part of the inner sedimentation tank 21, and the second communication pipe 32 penetrates through the filter screen 23. The wastewater entering from the second communication pipe 32 first enters the lower part of the inner sedimentation tank 21, and the generated flocculation particles are accumulated at the bottom of the inner sedimentation tank 21. After being intercepted by the filter screen 23, they will not flow upwards, which is beneficial to improve the sedimentation effect of the wastewater.

[0015] In order to slow down the flow speed of the wastewater and avoid the flocculation and sedimentation particles from floating at the bottom of the inner sedimentation tank 21 due to the impact force of the wastewater, a buffer cone cap 24 is arranged in the secondary treatment tank 2 below the second communication pipe 32. The buffer cone cap 24 is fixedly connected with the inner wall of the inner sedimentation tank 21 through a pull rod. After being buffered by the buffer cone cap 24, the flow speed of the wastewater can be reduced, the impact force on the flocculation and sedimentation particles is small, and the flocculation and sedimentation effect can be improved.

[0016] Further, in order to improve the treatment effect of the wastewater, a partition plate 25 is symmetrically arranged in the secondary treatment tank 2 outside the inner sedimentation tank 21. The upper end of the partition plate 25 is flush with the top of the secondary treatment tank 2, and the lower end of the partition plate 25 is spaced apart from the bottom of the secondary treatment tank 2. A sloping plate filter layer 26 and an activated carbon filter layer 27 are sequentially arranged in the space between the partition plate 25 and the inner wall of the secondary treatment tank 2 from bottom to top. After being treated by the inner sedimentation tank 21, the wastewater flows into the outside of the inner sedimentation tank 21. After being separated by the partition plate 25, the wastewater entering the outside of the inner sedimentation tank 21 enters the sloping plate filter layer 26 from below the partition plate 25. After being filtered by the sloping plate filter layer 26, the flocculation particles in the wastewater can be completely removed. After being filtered by the sloping plate filter layer 26, the wastewater enters the activated carbon filter layer 27 again. The activated carbon filter layer 27 has good adsorption property and can decolorize the wastewater, reduce the turbidity of the water, and improve the effect of wastewater purification and disposal.

Claims

1. A comprehensive treatment device for phosphorus pentoxide tailings wastewater, characterized in that: The system includes a primary treatment tank (1) and a secondary treatment tank (2). A wastewater conveying pipe (11) is installed on one side of the upper part of the primary treatment tank (1), and a first connecting pipe (12) is installed on the other side. An alkali addition pipe extending into the primary treatment tank (1) is installed above it. A first sewage discharge pipe (13) is installed at the bottom of the primary treatment tank (1). A mixer (3) is installed at the end of the first connecting pipe (12). A first dosing pipe, a second dosing pipe, and a stirring mechanism (31) are sequentially arranged along the water flow direction inside the mixer (3). The secondary treatment tank (2)... The bottom of the inner sedimentation tank (21) is provided with an inner sedimentation tank (21), the top of the inner sedimentation tank (21) is lower than the top of the secondary treatment tank (2), and a second drain pipe (22) is provided at the bottom of the secondary treatment tank (2) on both the inner and outer sides of the inner sedimentation tank (21). A drain valve is provided on both the first drain pipe (13) and the second drain pipe (22). A second connecting pipe (32) extending to the bottom of the inner sedimentation tank (21) is provided at the top of the mixer (3). An overflow tank (4) is provided at the upper part of the outer side of the secondary treatment tank (2), and an outlet pipe (41) is provided at the lower part of the overflow tank (4).

2. The comprehensive treatment device for phosphorus pentoxide tailings wastewater according to claim 1, characterized in that: The alkali addition pipeline includes an alkaline reagent storage tank (14) and an inlet pipe (15). The inlet pipe (15) extends to the lower part of the primary treatment tank (1). A sealing plate is installed at the lower end of the inlet pipe (15). Multiple distribution holes are evenly distributed in the lower part of the inlet pipe (15) located in the primary treatment tank (1). A first flow meter and a first control valve are sequentially installed on the inlet pipe (15) near the alkaline reagent storage tank (14).

3. The comprehensive treatment device for phosphorus pentoxide tailings wastewater according to claim 2, characterized in that: The drug inlet pipe (15) includes a first pipe section and a second pipe section, which are connected by a rotating joint (16). A drive motor (17) is mounted on the top of the primary treatment tank (1) via a bracket. A drive gear (18) is mounted on the output shaft of the drive motor (17). A driven gear (19) that meshes with the drive gear (18) is mounted on the second pipe section. Multiple stirring rods (110) are mounted on the lower part of the second pipe section.

4. The comprehensive treatment device for phosphorus pentoxide tailings wastewater according to claim 1, characterized in that: The first connecting pipe (12) is located above the wastewater conveying pipe (11), and the outlet of the wastewater conveying pipe (11) faces the bottom of the primary treatment tank (1). A seepage tank (111) is provided in the primary treatment tank (1) at the inlet of the first connecting pipe (12), and multiple seepage holes are evenly distributed at the bottom of the seepage tank (111).

5. The comprehensive treatment device for phosphorus pentoxide tailings wastewater according to claim 1, characterized in that: The first and second dosing pipelines have the same structure, both including a flocculant storage tank (33) and a dosing pipe (34), and the dosing pipe (34) is equipped with a second flow meter and a second control valve.

6. The comprehensive treatment device for phosphorus pentoxide tailings wastewater according to claim 1, characterized in that: The internal space of the inner sedimentation tank (21) gradually increases from top to bottom. A filter screen (23) is provided at the bottom of the inner sedimentation tank (21), and the second connecting pipe (32) passes through the filter screen (23).

7. The comprehensive treatment device for phosphorus pentoxide tailings wastewater according to claim 1, characterized in that: A buffer cone cap (24) is provided in the secondary treatment tank (2) below the second connecting pipe (32), and the buffer cone cap (24) is fixedly connected to the inner wall of the inner sedimentation tank (21) by a tie rod.

8. The comprehensive treatment device for phosphorus pentoxide tailings wastewater according to claim 1, characterized in that: A partition (25) is symmetrically installed in the secondary treatment tank (2) outside the inner sedimentation tank (21). The upper end of the partition (25) is flush with the top of the secondary treatment tank (2), and the lower end of the partition (25) is separated from the bottom of the secondary treatment tank (2). An inclined plate filter layer (26) and an activated carbon filter layer (27) are installed sequentially from bottom to top in the space between the partition (25) and the inner wall of the secondary treatment tank (2).

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