CN215288343U

CN215288343U - Device for recovering terephthalic acid from alkali decrement wastewater

Info

Publication number: CN215288343U
Application number: CN202122101704.6U
Authority: CN
Inventors: 李海娥; 朱佳伟; 倪康; 彭建良; 李祎
Original assignee: Jiaxing Huanke Environmental Protection New Material Technology Co ltd
Current assignee: Jiaxing Huanke Environmental Protection New Material Technology Co ltd
Priority date: 2021-09-01
Filing date: 2021-09-01
Publication date: 2021-12-24
Anticipated expiration: 2031-09-01

Abstract

The utility model relates to the technical field of chemical waste treatment, in particular to a device for recovering terephthalic acid from alkali decrement waste water, which comprises a neutralization reaction tank, a hydrocyclone, a solid-liquid separator, a waste water pump, a circulating water pump, an S-shaped heat dissipation elbow and an acid storage tank, wherein the neutralization reaction tank is provided with a first inlet, a second inlet and a liquid outlet, the liquid outlet is provided with a liquid outlet valve, the neutralization reaction tank is provided with a plurality of PH meters, the underflow opening of the hydrocyclone is communicated with the first inlet, the overflow opening of the hydrocyclone is communicated with the second inlet, the liquid outlet is communicated with the solid-liquid separator, the feeding opening of the hydrocyclone is connected with a three-way pipe, the waste water pump is communicated with the three-way pipe, the solid-liquid separator is communicated with the three-way pipe through the circulating water pump, a plurality of acid liquid pipes are arranged in the neutralization reaction tank, the acid liquid pipe is communicated with the acid storage tank, and an acid liquid regulating valve is arranged on the acid liquid pipe.

Description

Device for recovering terephthalic acid from alkali decrement wastewater

Technical Field

The utility model relates to a chemical industry waste material treatment technical field especially relates to a retrieve device of terephthalic acid in follow alkali decrement waste water.

Background

In the alkali deweighting wastewater of the polyester textile finishing production process, a large amount of sodium terephthalate exists, in the prior art, the terephthalic acid in the alkali deweighting wastewater is separated by adopting an acid precipitation mode, under mild conditions, the solubility of the terephthalic acid in water is very low, an acid feeding area is converged in a very large local terephthalic acid supersaturation area in the acid precipitation process, and the excessive terephthalic acid supersaturation degree can cause the crystallization process of the terephthalic acid to be mainly nucleated, so that the solid particles of the terephthalic acid are difficult to grow up, thereby causing the solid crystallinity of the terephthalic acid obtained by the conventional acid precipitation method to be low and small, causing the subsequent solid-liquid separation operations of filtering, washing, drying and the like to be difficult, and reducing the recovery efficiency of the alkali deweighting wastewater.

SUMMERY OF THE UTILITY MODEL

In order to solve the problems mentioned in the background art, the present invention aims to provide a device for recovering terephthalic acid from alkali weight reduction wastewater.

In order to realize the above object, the technical scheme of the utility model is that:

a device for recovering terephthalic acid from alkali decrement wastewater comprises a neutralization reaction tank, a hydrocyclone, a solid-liquid separator, a wastewater pump, a circulating water pump, an S-shaped heat dissipation elbow and an acid storage tank, wherein the top of the neutralization reaction tank is provided with a first inlet and a second inlet, the bottom of the neutralization reaction tank is provided with a liquid outlet, the liquid outlet is provided with a liquid outlet valve, the top, the middle and the bottom of the pipe wall of the neutralization reaction tank are respectively provided with a PH meter, the bottom flow port of the hydrocyclone is communicated with the first inlet, the overflow port of the hydrocyclone is communicated with the second inlet through a pipeline, the liquid outlet is communicated with the input port of the solid-liquid separator, the liquid outlet of the solid-liquid separator is communicated with the input port of the circulating water pump through a pipeline, and the feeding port of the hydrocyclone is connected with a three-way pipe, the waste water pump output port and circulating water pump' S output port respectively through the pipeline with the other both ends of three-way pipe intercommunication, S type heat dissipation return bend set firmly in the neutralization reaction jar and two ports of S type heat dissipation return bend all extend to the outside of neutralization reaction jar, many sour liquid pipes have been laid along vertical direction in the neutralization reaction jar, sour liquid pipe runs through the neutralization reaction jar, the sour liquid pipe pass through the pipeline with the acid storage tank intercommunication, be equipped with the acidizing fluid governing valve on the sour liquid pipe.

Furthermore, a filter is arranged on a pipeline communicating the waste water pump and the three-way pipe.

Furthermore, a flow meter is arranged on an output port of the acid storage tank.

Furthermore, a stirring shaft is vertically arranged in the neutralization reaction tank, and a motor for driving the stirring shaft to rotate is arranged at the top of the neutralization reaction tank.

Furthermore, the acid liquor pipe is arranged horizontally and is provided with a plurality of nozzles.

The utility model has the advantages that: the utility model discloses an additionally add a hydrocyclone, set up a three-way pipe on hydrocyclone's feed inlet, the other both ends of three-way pipe communicate with wastewater pump and circulating water pump respectively, go into hydrocyclone by circulating pump from the circulation thick liquids that solid-liquid separator flows, alkali decrement waste water is gone into in hydrocyclone by wastewater pump, be acidic circulation thick liquids and alkali decrement waste water after mixing in hydrocyclone, the dissolving reaction can take place for some tiny particle terephthalic acid in the circulation thick liquids, terephthalic acid after dissolving flows in with the retort once more through hydrocyclone's overflow mouth in, can not dissolve in the terephthalic acid granule discharges in with the retort equally through hydrocyclone's underflow mouth, add acid in with the PH value in reducing with the retort through acid liquid pipe in to the retort, this moment go into the terephthalic acid of dissolving in hydrocyclone and the alkali decrement waste water of wastewater pump can be at the terephthalic acid that can not dissolve in can dissolve The formic acid particles are deposited and grown, the small-particle terephthalic acid in the original circulating slurry is changed into large-particle terephthalic acid, the structural design is reasonable, the terephthalic acid with high crystallinity and large particles can be obtained, and the recovery efficiency of the alkali weight reduction wastewater is greatly improved.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

Description of the figure numbering: 1. neutralization reaction tank, 11, first inlet, 12, second inlet, 13, liquid outlet, 14, liquid outlet valve, 15, PH meter, 2, hydrocyclone, 21, tee pipe, 3, solid-liquid separator, 4, waste water pump, 5, circulating water pump, 6, S type heat dissipation return bend, 7, acid storage tank, 71, flowmeter, 8, acid liquid pipe, 81, acid liquid governing valve, 82, nozzle, 9, filter, 10, (mixing) shaft, 101, motor.

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. All other embodiments obtained by a person skilled in the art based on the embodiments of the present invention belong to the protection scope of the present invention.

As shown in figure 1, a device for recovering terephthalic acid from alkali decrement waste water comprises a neutralization reaction tank 1, a hydrocyclone 2, a solid-liquid separator 3, a waste water pump 4, a circulating water pump 5, an S-shaped heat dissipation elbow 6 and an acid storage tank 7, wherein the top of the neutralization reaction tank 1 is provided with a first liquid inlet 11 and a second liquid inlet 12, the bottom of the neutralization reaction tank 1 is provided with a liquid outlet 13, the liquid outlet 13 is provided with a liquid outlet valve 14, the top, the middle and the bottom of the pipe wall of the neutralization reaction tank 1 are respectively provided with a PH meter 15, the bottom flow port of the hydrocyclone 2 is communicated with the first liquid inlet 11, the overflow port of the hydrocyclone is communicated with the second liquid inlet 12 through a pipeline, the liquid outlet 13 is communicated with the input port of the solid-liquid separator 3, the liquid outlet of the solid-liquid separator 3 is communicated with the input port of the circulating water pump 5 through a pipeline, the feeding port of the hydrocyclone 2 is connected with a three-way pipe 21, the delivery outlet of wastewater pump 4 and circulating water pump 5' S delivery outlet communicate with the other both ends of three-way pipe 21 respectively through the pipeline, S type heat dissipation return bend 6 sets firmly in neutralization retort 1, and two ports of S type heat dissipation return bend 6 all extend to the outside of neutralization retort 1, two ports set up once on one, two sour liquid pipes 8 have been laid along vertical direction in neutralization retort 1, sour liquid pipe 8 runs through neutralization retort 1, the one end that sour liquid pipe 8 is located neutralization retort 1 outside is passed through the pipeline and is communicated with acid storage tank 7, be equipped with acidizing fluid governing valve 81 on sour liquid pipe 8.

When alkali reduction wastewater is treated, during the first reaction, the wastewater is pumped into a hydrocyclone 2 by a wastewater pump 4, then flows into a neutralization reaction tank 1 by the hydrocyclone 2, an acid liquid regulating valve 81 on two acid liquid pipes 8 is opened, so that acid liquid in an acid storage tank 7 flows into the neutralization reaction tank 1, the alkali reduction wastewater reacts with the acid liquid, a large amount of heat is generated during the reaction, cold water flows into a lower port of an S-shaped heat dissipation elbow pipe 6 and flows out of an upper port, a large amount of heat generated by the reaction is taken away, pH values of different regions in the neutralization reaction tank 1 are observed by three pH meters 15, the pH value of the upper part of the neutralization reaction tank 1 is adjusted to be 8.0-9.0, the pH value of the bottom of the neutralization reaction tank 1 is adjusted to be about 3.0-4.0, the pH value of a reaction region in the middle of the neutralization reaction tank 1 is adjusted to be 2.0, so that terephthalic acid dissolved in the wastewater is gradually crystallized and separated out, and after the pH is stabilized, closing the acid liquor regulating valve 81 and the waste water pump 4, opening the liquid outlet valve 14, allowing the solid phase and the liquid phase in the neutralization reaction tank 1 to flow into the solid-liquid separator 3, filtering the large-particle terephthalic acid by the solid-liquid separator 3, allowing the circulating slurry containing the small-particle terephthalic acid, the gel-like terephthalic acid and the liquid to flow into the hydrocyclone 2 by the circulating water pump 5, simultaneously opening the waste water pump 4 to pump the alkali-reduction wastewater into the hydrocyclone 2, mixing the acidic circulating slurry and the alkali-reduction wastewater in the hydrocyclone 2, allowing a part of the small-particle or gel-like terephthalic acid in the circulating slurry to undergo a dissolution reaction, allowing the dissolved terephthalic acid to flow into the neutralization reaction tank 1 again through an overflow port of the hydrocyclone 2, and discharging the undissolved terephthalic acid particles into the neutralization reaction tank 1 through a bottom flow port of the hydrocyclone 2, at the moment, the acid liquor regulating valve 81 is opened to add acid into the neutralization reaction tank 1 so as to reduce the pH value in the neutralization reaction tank 1, at the moment, the terephthalic acid dissolved in the hydrocyclone 2 and the terephthalic acid in the alkali reduction wastewater pumped by the wastewater pump 4 can deposit and grow on undissolved terephthalic acid particles, small-particle terephthalic acid in the original circulating slurry is changed into large-particle terephthalic acid, the acid liquor is continuously added, so that the crystallization of the terephthalic acid is more thorough, the liquid outlet valve 14 is opened again after the crystallization is finished, the solid-liquid separation is carried out, and the subsequent steps are circulated according to the above operation.

In this embodiment, the filter 9 is disposed on the pipeline connecting the waste water pump 4 and the three-way pipe 21, so as to remove mechanical impurities, fine dust particles, solid organic matter or inorganic matter particles in the waste water and improve the purity of terephthalic acid crystals.

In this embodiment, a flow meter 71 is disposed on an output port of the acid storage tank 7, so as to facilitate monitoring of the adding condition of the acid solution.

In this embodiment, a stirring shaft 10 is vertically disposed in the neutralization reaction tank 1, and a motor 101 for driving the stirring shaft 10 to rotate is disposed at the top of the neutralization reaction tank 1, so as to accelerate the reaction speed of the alkali weight reduction waste liquid and the acid liquid.

In this embodiment, the acid liquid pipe 8 is horizontally disposed and the acid liquid pipe 8 is provided with a plurality of nozzles 82, so that the acid liquid is added more uniformly.

The utility model adds a hydrocyclone 2 additionally, a three-way pipe 21 is arranged on the feeding port of the hydrocyclone 2, the other two ends of the three-way pipe 21 are respectively communicated with a waste water pump 4 and a circulating water pump 5, circulating slurry flowing out from a solid-liquid separator 3 is pumped into the hydrocyclone 2 by a circulating pump, alkali decrement waste water is pumped into the hydrocyclone 2 by the waste water pump 4, after the acidic circulating slurry and the alkali decrement waste water are mixed in the hydrocyclone 2, partial small-particle terephthalic acid in the circulating slurry can be subjected to a dissolution reaction, the dissolved terephthalic acid flows into a neutralization reaction tank 1 again through an overflow port of the hydrocyclone 2, undissolved terephthalic acid particles are discharged into the neutralization reaction tank 1 through a bottom flow port of the hydrocyclone 2, acid is added into the neutralization reaction tank 1 through an acid liquid pipe 8 to reduce the PH value in the neutralization reaction tank 1, at this time, the terephthalic acid dissolved in the hydrocyclone 2 and the terephthalic acid in the alkali weight reduction wastewater pumped by the wastewater pump 4 can deposit and grow on undissolved terephthalic acid particles, so that small-particle terephthalic acid in the original circulating slurry is changed into large-particle terephthalic acid.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not intended to limit the present invention, and all modifications, equivalents, improvements and the like that are within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A device for recovering terephthalic acid from alkali decrement wastewater is characterized by comprising a neutralization reaction tank (1), a hydrocyclone (2), a solid-liquid separator (3), a wastewater pump (4), a circulating water pump (5), an S-shaped heat dissipation elbow (6) and an acid storage tank (7), wherein a first liquid inlet (11) and a second liquid inlet (12) are arranged at the top of the neutralization reaction tank (1), a liquid outlet (13) is arranged at the bottom of the neutralization reaction tank (1), a liquid outlet valve (14) is arranged on the liquid outlet (13), PH meters (15) are respectively arranged at the top end, the middle part and the bottom end of the pipe wall of the neutralization reaction tank (1), a bottom flow port of the hydrocyclone (2) is communicated with the first liquid inlet (11), an overflow port of the hydrocyclone is communicated with the second liquid inlet (12) through a pipeline, and the liquid outlet (13) is communicated with an input port of the solid-liquid separator (3), a liquid outlet of the solid-liquid separator (3) is communicated with an input port of the circulating water pump (5) through a pipeline, a three-way pipe (21) is connected to a feeding port of the hydrocyclone (2), an output port of the waste water pump (4) and an output port of the circulating water pump (5) are respectively communicated with the other two ends of the three-way pipe (21) through pipelines, the S-shaped heat dissipation bent pipe (6) is fixedly arranged in the neutralization reaction tank (1), two ports of the S-shaped heat dissipation bent pipe (6) extend to the outside of the neutralization reaction tank (1), a plurality of acid liquid pipes (8) are distributed in the neutralization reaction tank (1) along the vertical direction, the acid liquid pipe (8) penetrates through the neutralization reaction tank (1), the acid liquid pipe (8) is communicated with the acid storage tank (7) through a pipeline, and an acid liquid regulating valve (81) is arranged on the acid liquid pipe (8).

2. The apparatus for recovering terephthalic acid from alkali weight reduction wastewater according to claim 1, wherein a filter (9) is provided on a pipe connecting said wastewater pump (4) and said tee pipe (21).

3. The apparatus for recovering terephthalic acid from alkali weight reduction wastewater according to claim 1, wherein a flow meter (71) is provided at an output port of the acid storage tank (7).

4. The apparatus for recovering terephthalic acid from alkali weight reduction wastewater according to claim 1, wherein a stirring shaft (10) is vertically disposed in the neutralization reaction tank (1), and a motor (101) for driving the stirring shaft (10) to rotate is disposed at the top of the neutralization reaction tank (1).

5. The apparatus for recovering terephthalic acid from alkali weight reduction wastewater according to claim 1, wherein the acid liquid pipe (8) is horizontally disposed and a plurality of nozzles (82) are disposed on the acid liquid pipe (8).