Alkaline wastewater treatment system

Abstract

The invention relates to the field of wastewater treatment, in particular to an alkaline wastewater treatment system which comprises a coagulant adding mechanism arranged on a coagulating basin a, the coagulant adding mechanism is used for mixing coagulant powder and water to prepare a coagulant in proportion, and a spiral water passing pipe is arranged on the coagulant adding mechanism; sewage and coagulants in the sewage concentration tank are pumped into the top of the spiral water passing pipe for continuous flowing mixing, two groups of coagulant adding mechanisms are arranged, and the other group of coagulant adding mechanisms is arranged on the coagulation tank b; and the reflux metering pumps are arranged on the coagulating basin a and the coagulating basin b, and the two reflux metering pumps are communicated with the reflux pipe and are used for quantitatively pumping the returned pressure filtrate into the coagulating basin a and the coagulating basin b. According to the invention, the coagulant and sewage can be fully mixed, large-scale stirring equipment is not needed, energy is greatly reduced, and in addition, by setting an accurate calculation formula, calculation can be carried out in real time according to the formula, so that the pressure filtrate can be supplemented as the coagulant to be supplemented into the coagulating basin a and the coagulating basin b.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and in particular to an alkaline wastewater treatment system. Background Art

[0002] Paint spraying wastewater is alkaline wastewater, which contains a large amount of paint particles. Its water quality depends on the paint, solvent and additives used. The core of the commonly used paint spraying wastewater treatment method is to add coagulant A and coagulant B for coagulation and sedimentation, and then separate the mud and water to complete the treatment process.

[0003] The Chinese patent with the announcement number CN212151865U discloses a resource treatment system for alkaline wastewater, including an alkaline wastewater collection tank, the alkaline wastewater collection tank is used to collect alkaline wastewater; a dosing device, the dosing device is used to add flocculants, the flocculants are used to form flocs with the alkaline wastewater; a first solid-liquid separation system connected to the alkaline wastewater collection tank, the first solid-liquid separation system is used to perform solid-liquid separation on the flocs; a solid acidification system connected to the first solid separation system, the solid formed by the solid-liquid separation of the first solid-liquid separation system enters the solid acidification system, the solid acidification system has an acid addition device, the acid addition device is used to add acid to dissolve the solid part; a second solid-liquid separation system connected to the solid acidification system. The utility model can greatly improve the quality of recovered TA, reduce the dosage of flocculants and other agents, and reduce the generation of solid waste sludge.

[0004] However, the above-mentioned disclosed scheme has the following shortcomings: Although it is mentioned that the filtrate after solid-liquid separation is returned to the front stage for use as a coagulant to save the amount of coagulant used, there is a lack of specific methods and means of use. In the actual process, the filtrate after solid-liquid separation is not added to the coagulation tank by appropriate means, which will seriously interfere with the coagulation effect of the coagulation tank and reduce the stability of the sewage treatment system. In addition, the addition of a stirring device in the coagulation tank in the prior art greatly increases the energy consumption. Summary of the invention

[0005] The purpose of the present invention is to propose an alkaline wastewater treatment system to address the problems in the background technology that the installation of a stirring device in the coagulation tank increases energy consumption, and the reflux of the filtrate after solid-liquid separation used as a coagulant easily causes the instability of the entire system.

[0006] The technical solution of the present invention is: an alkaline wastewater treatment system, comprising a sewage concentration tank, a coagulation tank a, a coagulation tank b, a sedimentation tank and a mud-water separation device arranged in sequence in the sewage flow direction, the mud-water separation device comprising a sludge pump for extracting sludge from the sedimentation tank, a plate-frame filter press for filtering the sludge, and the filtrate treated by the plate-frame filter press is transported to the sewage concentration tank through a water pump and a reflux pipe; and also comprising:

[0007] The coagulant adding mechanism is arranged on the coagulation tank a. The coagulant adding mechanism is used to mix the coagulant powder and water so that they are configured into a coagulant in proportion. The power source of the mixing is the impact force of the liquid reflux in the reflux pipe. The coagulant adding mechanism is provided with a spiral water pipe. The sewage in the sewage concentration tank and the coagulant are pumped into the top of the spiral water pipe for continuous flow mixing. Two groups of coagulant adding mechanisms are arranged, and the other group is arranged on the coagulation tank b.

[0008] And a reflux metering pump is arranged on the coagulation tank a and the coagulation tank b through a mounting frame. Both reflux metering pumps are connected to the reflux pipe, and the reflux filtrate is quantitatively pumped into the coagulation tank a and the coagulation tank b according to calculation.

[0009] Preferably, the coagulant adding mechanism comprises a mixing component and a power component, the mixing component is used to mix the coagulant powder and water according to a proportion, and the power component is used to drive the mixing component to work.

[0010] Preferably, the mixing assembly includes a barrel body arranged on the coagulation tank a, a partition a and a partition b arranged side by side in the barrel body, a rotating shaft rotatably arranged at the bottom of the barrel body and passing through the partition a, a spiral stirring blade arranged on the rotating shaft, and a coagulant metering pump arranged on the partition b to pump the liquid coagulant below into the spiral water pipe; a quantitative dosing pipe and a quantitative water adding pipe are arranged on the barrel body, the quantitative dosing pipe passes through the partition b from above, and the quantitative dosing pipe passes through the peripheral wall of the barrel body and extends into the barrel body.

[0011] Preferably, the power assembly includes a rotating rod rotatably arranged on the barrel body, an actuating fan blade and a driving bevel gear arranged at both ends of the rotating rod, and a driven bevel gear arranged on the rotating shaft, the driven bevel gear and the driving bevel gear are meshed, the rotating rod is inserted into the reflux pipe, and the actuating fan blade is driven to rotate by the filtrate flowing in the reflux pipe.

[0012] Preferably, the rotation speed of the driven bevel gear is lower than that of the driving bevel gear.

[0013] Preferably, a coagulant concentration detection device is provided at the position where the sewage on coagulation tank a flows to the coagulation tank b, a coagulant concentration detection device is provided at the position where the sewage on coagulation tank b flows to the sedimentation tank, and a coagulant concentration monitoring device for detecting the coagulant concentration in the filtrate is provided on the reflux pipe.

[0014] Preferably, the calculation method of the amount of press filtrate to be replenished in the coagulation tank a is as follows: the setting parameters include the amount V of press filtrate to be replenished in the coagulation tank a h , the coagulant concentration setting value C at the position where the sewage flows from coagulation tank a to coagulation tank b m , the current value of the coagulant concentration C at the location where the sewage flows from coagulation tank a to coagulation tank b d , the coagulant concentration in the filtrate is C h , the amount of water V in the coagulation tank a y, the calculation formula is:

[0015]

[0016] Preferably, the calculation method of the amount of press filtrate to be replenished in the coagulation tank b is as follows: the setting parameters include the amount V of press filtrate to be replenished in the coagulation tank b h , the coagulant concentration setting value C at the location where the sewage flows from the coagulation tank b to the sedimentation tank m , the current value of the coagulant concentration C at the location where the sewage flows from the coagulation tank b to the sedimentation tank d , the coagulant concentration in the filtrate is C h , the amount of water V in the coagulation tank b y , the calculation formula is:

[0017]

[0018] Compared with the prior art, the present invention has the following beneficial technical effects: after the sewage enters the top of the spiral water pipe, it is mixed with a quantitative and continuously added coagulant, and is discharged into coagulation tank a and coagulation tank b after flowing in the spiral water pipe, so that the coagulant and sewage can be fully mixed, and there is no need to set up large-scale stirring equipment, which greatly reduces energy. In addition, by setting an accurate calculation formula, the filtrate can be calculated in real time according to the formula to replenish the filtrate as a coagulant into coagulation tank a and coagulation tank b, thereby maintaining the stability of the system and ensuring the coagulation effect, and also reducing the consumption of the coagulant. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 and Figure 2 Each of them is a stereogram of an embodiment of the present invention;

[0020] Figure 3 for Figure 1 A partial structural diagram of

[0021] Figure 4 is the internal schematic diagram of coagulation tank a;

[0022] Figure 5 for Figure 4 sectional view of .

[0023] Figure numerals: 1. sewage concentration tank; 2. coagulation tank a; 3. coagulation tank b; 4. sedimentation tank; 5. mud-water separation device; 6. return pipe; 7. water pump; 8. mounting seat; 9. barrel; 10. spiral water pipe; 11. water inlet pipe; 12. partition a; 13. partition b; 14. rotating shaft; 15. spiral stirring blade; 16. coagulant metering pump; 17. quantitative dosing pipe; 18. quantitative water adding pipe; 19. liquid level meter; 20. water guide pipe a; 21. driven bevel gear; 22. rotating rod; 23. driving blade; 24. driving bevel gear; 25. water guide pipe b; 26. final discharge pipe; 27. mounting bracket; 28. return metering pump. DETAILED DESCRIPTION

[0024] Embodiment 1

[0025] like Figure 1-Figure 3 As shown, an alkaline wastewater treatment system proposed by the present invention includes a sewage concentration tank 1, a coagulation tank a2, a coagulation tank b3, a sedimentation tank 4 and a mud-water separation device 5 which are sequentially arranged in the sewage flow direction, the coagulation tank b3 and the sedimentation tank 4 are connected through a water guide pipe b25 arranged on the top, a final discharge pipe 26 is arranged on the top of the sedimentation tank 4, a coagulant A is put into the coagulation tank a2, and a coagulant B is put into the coagulation tank b3. In this embodiment, the coagulant A is PAC, PAC polyaluminium chloride, and the coagulant B is PAM, which is an organic polymer agent used as a coagulant aid. The mud-water separation device 5 includes a sludge pump for extracting the sludge in the sedimentation tank 4, a plate-frame filter press for filtering the sludge, and the filtrate treated by the plate-frame filter press is transported to the sewage concentration tank 1 through a water pump and a reflux pipe 6; and also includes:

[0026] A coagulant adding mechanism is arranged on the coagulation tank a2. The coagulant adding mechanism is used to mix the coagulant powder and water so that they are configured into a coagulant in proportion. The power source of the mixing is the impact force of the liquid reflux in the reflux pipe 6. A spiral water pipe 10 is arranged on the coagulant adding mechanism. The sewage and the coagulant in the sewage concentration tank 1 are pumped into the top of the spiral water pipe 10 for continuous flow mixing. Specifically, a water pump 7 is arranged on the sewage concentration tank 1. The water pump 7 pumps the sewage into the spiral water pipe 10 through the water inlet pipe 11. Two groups of coagulant adding mechanisms are arranged. The other group is arranged on the coagulation tank b3. The two groups of coagulant adding mechanisms respectively add coagulant A and coagulant B to the sewage. The top of the coagulation tank a2 is connected to the top of the next spiral water pipe 10 through the water pipe a20. In order to save energy, the height of the coagulation tank b3 is lower than that of the coagulation tank a2. The sewage flows into the spiral water pipe 10 from the water pipe a20 by gravity.

[0027] And the reflux metering pump 28 is set on the coagulation tank a2 and the coagulation tank b3 through the mounting frame 27. The two reflux metering pumps 28 are connected to the reflux pipe 6. According to the calculation, the reflux filtrate is quantitatively pumped into the coagulation tank a2 and the coagulation tank b3, thereby reducing the consumption of the coagulant.

[0028] Embodiment 2

[0029] like Figure 1 , Figure 4 and Figure 5 As shown, an alkaline wastewater treatment system proposed by the present invention, compared with the first embodiment, this embodiment introduces the structure of the coagulant adding mechanism in detail.

[0030] The coagulant adding mechanism comprises a mixing component and a power component. The mixing component is used to mix the coagulant powder and water according to a proportion, and the power component is used to drive the mixing component to work.

[0031] The mixing assembly includes a barrel body 9 arranged on the coagulation tank a2 through a mounting seat 8, a partition a12 and a partition b13 arranged side by side in the barrel body 9, a rotating shaft 14 rotatably arranged at the bottom of the barrel body 9 and passing through the partition a12, a spiral stirring blade 15 arranged on the rotating shaft 14, and a coagulant metering pump 16 arranged on the partition b13 to pump the liquid coagulant below into the spiral water pipe 10, and the coagulant delivery amount and the sewage pumping amount form a set ratio; a quantitative dosing pipe 17 and a quantitative water pipe 18 are arranged on the barrel body 9, and the quantitative dosing pipe 17 passes through the partition b13 from above, and the quantitative dosing pipe 17 passes through the spiral water pipe 10. The peripheral wall of the barrel body 9 extends into the barrel body 9, the quantitative dosing pipe 17 is connected to the external quantitative dosing equipment, and the quantitative water adding pipe 18 is connected to the quantitative water adding equipment. The coagulant powder and water are mixed between the partition a12 and the partition b13 to form a liquid coagulant, and then pumped into the spiral water pipe 10 through the coagulant metering pump 16. In order to ensure that the input end of the coagulant metering pump 16 can smoothly draw the coagulant, a liquid level meter 19 is set on the partition b13. The liquid level meter 19 detects the liquid level under the partition b13 to ensure the liquid level height. When the liquid level is too low, the quantitative dosing pipe 17 and the quantitative water adding pipe 18 are used to add medicine and water in time.

[0032] The power assembly includes a rotating rod 22 rotatably arranged on the barrel 9, an urging blade 23 and a driving bevel gear 24 arranged at both ends of the rotating rod 22, and a driven bevel gear 21 arranged on the rotating shaft 14. The driven bevel gear 21 and the driving bevel gear 24 are meshed, and the rotating rod 22 is inserted into the reflux pipe 6. The urging blade 23 is driven to rotate by the filtrate flowing in the reflux pipe 6. The speed of the driven bevel gear 21 is lower than that of the driving bevel gear 24, thereby completing the speed reduction rotation, and preventing the spiral stirring blade 15 from rotating too fast to destroy the components of the coagulant.

[0033] Embodiment 3

[0034] like Figure 1 As shown, an alkaline wastewater treatment system proposed in the present invention, compared with the first or second embodiment, this embodiment introduces in detail how to add the filtrate to the coagulation tank a2 and the coagulation tank b3.

[0035] A coagulant concentration detection device is provided at the position where the sewage on the coagulation tank a2 flows to the coagulation tank b3, that is, at the end of the coagulation reaction. A coagulant concentration detection device is provided at the position where the sewage on the coagulation tank b3 flows to the sedimentation tank 4, that is, at the end of the coagulation reaction. A coagulant concentration monitoring device for detecting the coagulant concentration in the filtrate is provided on the reflux pipe 6.

[0036] Calculation method for the amount of press filtrate to be replenished in coagulation tank a2: The set parameters include the amount of press filtrate to be replenished in coagulation tank a2 V h , the coagulant concentration setting value C at the position where the sewage flows from coagulation tank a2 to coagulation tank b3 m , the current value of the coagulant concentration C at the location where the sewage flows from coagulation tank a2 to coagulation tank b3 d , the concentration of coagulant in the filtrate, specifically the concentration of coagulant A is C h , the amount of water V in the coagulation tank a2 y , the calculation formula is:

[0037]

[0038] Calculation method for the amount of press filtrate to be replenished in coagulation tank b3: The set parameters include the amount of press filtrate to be replenished in coagulation tank b3 V h , the coagulant concentration setting value C at the position where the sewage flows from the coagulation tank b3 to the sedimentation tank 4 m , the current value of the coagulant concentration C at the location where the sewage flows from the coagulation tank b3 to the sedimentation tank 4 d , the concentration of coagulant in the filtrate, specifically the concentration of coagulant B is C h , the amount of water V in the coagulation tank b3 y , the calculation formula is:

[0039]

[0040] Here is an example to illustrate the formula:

[0041] The coagulant concentration was set to 10 mg / L.

[0042] The current coagulant concentration in the coagulation tank is 9 mg / L.

[0043] The coagulant concentration in the filtrate was 20 mg / L.

[0044] The volume of sewage in coagulation tank a2 and coagulation tank b3 is 1000L.

[0045] Substituting these values ​​into the formula:

[0046] That is, when the coagulant is added according to the set amount, the coagulant content in the sewage at the end of the coagulation reaction does not reach the set value, which means that the coagulant content is insufficient. By adding the filtrate to the corresponding coagulation tank for use as a coagulant, the coagulant consumption is reduced. The coagulant and water ratio does not need to be adjusted in real time, but the coagulation reaction is corrected through the filtrate.

[0047] Embodiment 4

[0048] The alkaline wastewater treatment system proposed in the present invention introduces a control system in detail compared with the first embodiment, the second embodiment or the third embodiment.

[0049] The control system is connected to each coagulant concentration detection device and the liquid level meter 19 for data transmission, and the control system is connected to the water pump 7 , the coagulant metering pump 16 and the reflux metering pump 28 for control.

[0050] In summary, when the present invention is in use, the sewage enters the top of the spiral water pipe 10 and is mixed with the quantitatively and continuously added coagulant. After flowing in the spiral water pipe, it is discharged into the coagulation tank a2 and the coagulation tank b3, so that the coagulant and the sewage can be fully mixed. There is no need to set up large-scale stirring equipment, which greatly reduces energy. In addition, by setting an accurate calculation formula, the filtrate can be replenished as a coagulant to the coagulation tank a2 and the coagulation tank b3 in real time according to the formula, thereby maintaining the stability of the system and ensuring the coagulation effect, and also reducing the consumption of the coagulant.

[0051] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto, and various changes can be made within the knowledge scope of technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. An alkaline wastewater treatment system, comprising a sewage concentration tank (1), a coagulation tank a (2), a coagulation tank b (3), a sedimentation tank (4) and a mud-water separation device (5) arranged in sequence in the sewage flow direction, the mud-water separation device (5) comprising a sludge pump for extracting sludge from the sedimentation tank (4), a plate-frame filter press for filtering the sludge, and the filtrate treated by the plate-frame filter press is transported to the sewage concentration tank (1) through a water pump and a reflux pipe (6); characterized in that: Also includes: A coagulant adding mechanism is arranged on the coagulation tank a (2). The coagulant adding mechanism is used to mix coagulant powder and water so that they are configured into a coagulant in proportion. The power source of the mixing is the impact force of the liquid reflux in the reflux pipe (6). A spiral water pipe (10) is arranged on the coagulant adding mechanism. The sewage and coagulant in the sewage concentration tank (1) are pumped into the top of the spiral water pipe (10) for continuous flow mixing. Two groups of coagulant adding mechanisms are arranged, and the other group is arranged on the coagulation tank b (3); And a reflux metering pump (28) is arranged on the coagulation tank a (2) and the coagulation tank b (3) through a mounting frame (27). The two reflux metering pumps (28) are both connected to the reflux pipe (6) and quantitatively pump the refluxed filtrate into the coagulation tank a (2) and the coagulation tank b (3) according to calculation.

2. The alkaline wastewater treatment system according to claim 1, characterized in that: The coagulant adding mechanism comprises a mixing component and a power component. The mixing component is used to mix the coagulant powder and water according to a proportion, and the power component is used to drive the mixing component to work.

3. The alkaline wastewater treatment system according to claim 2, characterized in that: The mixing assembly comprises a barrel (9) arranged on a coagulation tank a (2), a partition a (12) and a partition b (13) arranged side by side in the barrel (9), a rotating shaft (14) rotatably arranged at the bottom of the barrel (9) and passing through the partition a (12), a spiral stirring blade (15) arranged on the rotating shaft (14), and a coagulant metering pump (16) arranged on the partition b (13) for pumping the liquid coagulant below into the spiral water pipe (10); a quantitative dosing pipe (17) and a quantitative water adding pipe (18) are arranged on the barrel (9), the quantitative dosing pipe (17) passes through the partition b (13) from above, and the quantitative dosing pipe (17) passes through the peripheral wall of the barrel (9) and extends into the barrel (9).

4. The alkaline wastewater treatment system according to claim 3, characterized in that: The power assembly comprises a rotating rod (22) rotatably arranged on a barrel (9), an urging blade (23) and a driving bevel gear (24) arranged at both ends of the rotating rod (22), and a driven bevel gear (21) arranged on a rotating shaft (14). The driven bevel gear (21) and the driving bevel gear (24) are meshed. The rotating rod (22) is inserted into a return pipe (6), and the urging blade (23) is driven to rotate by the filtrate flowing in the return pipe (6).

5. The alkaline wastewater treatment system according to claim 4, characterized in that: The rotation speed of the driven bevel gear (21) is lower than that of the driving bevel gear (24).

6. The alkaline wastewater treatment system according to claim 1, characterized in that: A coagulant concentration detection device is provided at the position where the sewage on the coagulation tank a (2) flows to the coagulation tank b (3), a coagulant concentration detection device is provided at the position where the sewage on the coagulation tank b (3) flows to the sedimentation tank (4), and a coagulant concentration monitoring device for detecting the coagulant concentration in the filtrate is provided on the return pipe (6).

7. The alkaline wastewater treatment system according to claim 6, characterized in that: Calculation method for the amount of press filtrate to be replenished in coagulation tank a(2): The set parameters include the amount of press filtrate to be replenished in coagulation tank a(2) V h , the coagulant concentration setting value C at the location where the sewage flows from coagulation tank a (2) to coagulation tank b (3) m , the current value of the coagulant concentration C at the location where the sewage flows from coagulation tank a (2) to coagulation tank b (3) d , the coagulant concentration in the filtrate is C h , the amount of water V in the coagulation tank a(2) y , the calculation formula is:

8. The alkaline wastewater treatment system according to claim 6, characterized in that: Calculation method for the amount of press filtrate to be replenished in coagulation tank b(3): The set parameters include the amount of press filtrate to be replenished in coagulation tank b(3) V h , the coagulant concentration setting value C at the location where the sewage flows from the coagulation tank b (3) to the sedimentation tank (4) m , the current value of the coagulant concentration C at the location where the sewage flows from the coagulation tank b (3) to the sedimentation tank (4) d , the coagulant concentration in the filtrate is C h , the amount of water V in the coagulation tank b(3) y , the calculation formula is:

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