CN220098829U - System for recovering magnesium hydroxide in basic sludge and using magnesium hydroxide as heavy metal remover - Google Patents
System for recovering magnesium hydroxide in basic sludge and using magnesium hydroxide as heavy metal remover Download PDFInfo
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- CN220098829U CN220098829U CN202321532515.7U CN202321532515U CN220098829U CN 220098829 U CN220098829 U CN 220098829U CN 202321532515 U CN202321532515 U CN 202321532515U CN 220098829 U CN220098829 U CN 220098829U
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- Prior art keywords
- magnesium hydroxide
- tank
- sludge
- dehydrator
- heavy metal
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- 239000000347 magnesium hydroxide Substances 0.000 title claims abstract description 108
- 229910001862 magnesium hydroxide Inorganic materials 0.000 title claims abstract description 108
- VTHJTEIRLNZDEV-UHFFFAOYSA-L magnesium dihydroxide Chemical compound [OH-].[OH-].[Mg+2] VTHJTEIRLNZDEV-UHFFFAOYSA-L 0.000 title claims abstract description 107
- 239000010802 sludge Substances 0.000 title claims abstract description 82
- 229910001385 heavy metal Inorganic materials 0.000 title claims abstract description 24
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 claims abstract description 43
- 238000011084 recovery Methods 0.000 claims abstract description 41
- 238000004064 recycling Methods 0.000 claims abstract description 14
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 12
- 239000000706 filtrate Substances 0.000 claims abstract description 5
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 44
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 31
- 230000001105 regulatory effect Effects 0.000 claims description 20
- 238000011010 flushing procedure Methods 0.000 claims description 6
- 238000000926 separation method Methods 0.000 abstract description 5
- 238000006477 desulfuration reaction Methods 0.000 abstract description 2
- 230000023556 desulfurization Effects 0.000 abstract description 2
- 229910052602 gypsum Inorganic materials 0.000 abstract description 2
- 239000010440 gypsum Substances 0.000 abstract description 2
- 230000007613 environmental effect Effects 0.000 abstract 1
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 description 10
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 8
- 229910052943 magnesium sulfate Inorganic materials 0.000 description 5
- 235000019341 magnesium sulphate Nutrition 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 229910000019 calcium carbonate Inorganic materials 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 2
- 230000018044 dehydration Effects 0.000 description 2
- 238000006297 dehydration reaction Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000920 calcium hydroxide Substances 0.000 description 1
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 1
- 159000000007 calcium salts Chemical class 0.000 description 1
- 238000005352 clarification Methods 0.000 description 1
- 230000001112 coagulating effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000003657 drainage water Substances 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 159000000003 magnesium salts Chemical class 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Abstract
The utility model discloses a system for recycling magnesium hydroxide in basic sludge to be used as a heavy metal removing agent, which comprises a sludge concentration tank, a pH adjusting tank, a calcium sulfate dehydrator, a magnesium hydroxide recycling tank, a magnesium hydroxide dehydrator and a magnesium hydroxide metering box; the sludge concentration tank is connected with the pH adjusting tank, the bottom of the pH adjusting tank is connected with the calcium sulfate dehydrator, the filtrate outlet of the calcium sulfate dehydrator is connected with the magnesium hydroxide recovery tank, the bottom of the magnesium hydroxide recovery tank is connected with the magnesium hydroxide dehydrator, and the magnesium hydroxide dehydrator is connected with the magnesium hydroxide metering box. The utility model has simple structure, the recovered magnesium hydroxide can be used as heavy metal removing agent, the recovered calcium sulfate can be conveyed to a desulfurization system for producing gypsum, and the recovery and separation method is relatively simple, so that the recycling of sludge has better economic benefit and environmental protection benefit.
Description
Technical Field
The utility model belongs to the field of sludge recycling of a water treatment system, and particularly relates to a system for recycling magnesium hydroxide in basic sludge and using the magnesium hydroxide as a heavy metal remover.
Background
The surplus sludge generated by the coagulating and clarifying water treatment system based on the double-alkali method contains a large amount of alkaline substances such as calcium carbonate, magnesium hydroxide and the like, and the waste of resources can be caused by landfill disposal after the direct dehydration of the part of sludge. Especially for waste water with relatively high magnesium hardness such as mine drainage water, the magnesium hydroxide content in the residual sludge is relatively high, the magnesium hydroxide in the sludge can be recycled and used as a heavy metal remover, and as more substances such as calcium carbonate and calcium hydroxide exist in the basic sludge, the direct recycling as the heavy metal remover can lead to other impurities to be brought in, so that the water quality of a recycling system is poor, the sludge amount is increased, and therefore, a system for recycling the magnesium hydroxide in the basic sludge is needed, the separation of calcium and magnesium in the sludge is realized, and the recycling of the magnesium hydroxide sludge is finally realized.
Disclosure of Invention
Aiming at the technical problems existing at the present stage, the utility model aims to provide a system for recovering magnesium hydroxide in basic sludge and using the magnesium hydroxide as a heavy metal remover, which can realize separation and purification of magnesium hydroxide in sludge, recover magnesium hydroxide and simultaneously can separate and obtain calcium sulfate, thereby improving the utilization rate of sludge resources.
In order to achieve the above purpose, the utility model adopts the following technical scheme:
a system for recycling magnesium hydroxide in basic sludge to be used as a heavy metal remover comprises a sludge concentration tank, a pH adjusting tank, a calcium sulfate dehydrator, a magnesium hydroxide recycling tank, a magnesium hydroxide dehydrator and a magnesium hydroxide metering box;
the sludge concentration tank is connected with the pH adjusting tank, the bottom of the pH adjusting tank is connected with the calcium sulfate dehydrator, the filtrate outlet of the calcium sulfate dehydrator is connected with the magnesium hydroxide recovery tank, the bottom of the magnesium hydroxide recovery tank is connected with the magnesium hydroxide dehydrator, and the magnesium hydroxide dehydrator is connected with the magnesium hydroxide metering box.
Further, the device also comprises a sulfuric acid dosing unit, wherein the sulfuric acid dosing unit is connected with a sulfuric acid dosing interface arranged on the pH adjusting tank.
Further, an adjusting tank stirrer and an adjusting tank pH meter are arranged in the pH adjusting tank.
Further, the device also comprises a sodium hydroxide dosing unit, wherein the sodium hydroxide dosing unit is connected with a sodium hydroxide dosing interface arranged on the magnesium hydroxide recovery tank.
Further, a recovery tank stirrer and a recovery tank pH meter are arranged in the magnesium hydroxide recovery tank.
Further, a densitometer is arranged on the magnesium hydroxide metering box.
Further, the bottom of the sludge concentration tank is connected with the pH adjusting tank through a sludge discharge pump of the concentration tank.
Further, the bottom of the pH adjusting tank is connected with a calcium sulfate dehydrator through a sludge conveying pump of the adjusting tank.
Further, the bottom of the magnesium hydroxide recovery tank is connected with a magnesium hydroxide dehydrator through a recovery tank sludge conveying pump.
Further, the sludge pump of the concentration tank, the sludge pump of the regulating tank, the sludge pump of the recovery tank and the magnesium hydroxide pump are connected with a flushing device.
Compared with the prior art, the utility model has the beneficial effects that:
according to the utility model, the sulfuric acid dosing interface is arranged on the pH regulating tank, sulfuric acid is added into basic sludge, so that magnesium hydroxide is precipitated and dissolved, calcium carbonate is precipitated and converted into calcium sulfate, solid-liquid separation is realized through the sludge dewatering system, so that calcium salt and magnesium salt in the sludge are separated, and then the sodium hydroxide dosing interface is arranged on the magnesium hydroxide recovery tank, so that the magnesium sulfate is converted into magnesium hydroxide.
Drawings
FIG. 1 is a schematic diagram of a system for recovering magnesium hydroxide as heavy metal remover from basic sludge;
wherein, 1-a sludge concentration tank; 2-a sludge pump of a concentration tank; 3-a pH adjusting tank; 4-a regulating tank stirrer; 5-adjusting the pH meter of the pool; 6-a sludge conveying pump of the regulating tank; 7-calcium sulfate dehydrator; 8-a magnesium hydroxide recovery tank; 9-a recovery tank stirrer; 10-a recovery tank pH meter; 11-a recovery tank sludge delivery pump; 12-a magnesium hydroxide dehydrator; 13-a magnesium hydroxide storage hopper; 14-a screw metering conveyor; 15-a magnesium hydroxide metering box; 16-densitometer; 17-magnesium hydroxide delivery pump; an 18-sulfuric acid dosing unit; 19-sodium hydroxide dosing unit.
Detailed Description
The utility model is described in further detail below with reference to the accompanying drawings.
Referring to fig. 1, a system for recovering magnesium hydroxide from basic sludge for use as a heavy metal removal agent mainly comprises a sludge concentration tank 1, a concentration tank sludge discharge pump 2, a pH adjusting tank 3, an adjusting tank stirrer 4, an adjusting tank pH meter 5, an adjusting tank sludge delivery pump 6, a calcium sulfate dehydrator 7, a magnesium hydroxide recovery tank 8, a recovery tank stirrer 9, a recovery tank pH meter 10, a recovery tank sludge delivery pump 11, a magnesium hydroxide dehydrator 12, a magnesium hydroxide storage hopper 13, a screw metering conveyor 14, a magnesium hydroxide metering tank 15, a densimeter 16, a magnesium hydroxide delivery pump 17, a sulfuric acid dosing unit 18, and a sodium hydroxide dosing unit 19.
The bottom of the sludge concentration tank 1 is connected with the pH regulating tank 3 through a concentration tank sludge discharge pump 2, the bottom interface of the pH regulating tank 3 is connected with a calcium sulfate dehydrator 7 through a regulating tank sludge conveying pump 6, a filtrate outlet pipe of the calcium sulfate dehydrator 7 is connected to a magnesium hydroxide recovery tank 8, the bottom interface of the magnesium hydroxide recovery tank 8 is connected with a magnesium hydroxide dehydrator 12 through a recovery tank sludge conveying pump 11, a solid outlet discharged mud cake of the magnesium hydroxide dehydrator 12 enters a magnesium hydroxide storage hopper 13, the magnesium hydroxide storage hopper 13 is connected with a magnesium hydroxide metering box 15 through a screw metering conveyor 14, and the magnesium hydroxide metering box 15 is connected with a dosing point through a magnesium hydroxide conveying pump 17.
The pH adjusting tank 3 is provided with a sulfuric acid dosing interface which is connected with a sulfuric acid dosing unit 18. The pH adjusting tank 3 is internally provided with an adjusting tank stirrer 4 and an adjusting tank pH meter 5.
The magnesium hydroxide recovery tank 8 is provided with a sodium hydroxide dosing interface which is connected with a sodium hydroxide dosing unit 19. The magnesium hydroxide recovery tank 8 is internally provided with a recovery tank stirrer 9 and a recovery tank pH meter 10.
The magnesium hydroxide metering box 15 is provided with a densitometer 16.
The concentration tank sludge pump 2, the adjustment tank sludge transfer pump 6, the recovery tank sludge transfer pump 11 and the magnesium hydroxide transfer pump 17 are all provided with flushing devices, and flushing is performed by flushing water.
The working process of the utility model is as follows:
the residual sludge discharged from the lime softening clarification tank regularly enters a sludge concentration tank 1 for storage, the sludge in the sludge concentration tank 1 is conveyed to a pH regulating tank 3 through a bottom concentration tank sludge discharge pump 2, a dosing pump of a sulfuric acid dosing unit 18 is started, the pH value of the regulating tank 3 is maintained within a range of 7-8 through adding sulfuric acid, magnesium hydroxide and calcium carbonate in the sludge react with dilute sulfuric acid added in the pH regulating tank 3, a regulating tank stirrer 4 is started, and the magnesium sulfate and the calcium sulfate are uniformly mixed and react under the stirring of the regulating tank stirrer 4, so that water-soluble magnesium sulfate and calcium sulfate precipitate is generated. The reacted sludge is conveyed to a calcium sulfate dehydrator 7 through a sludge conveying pump 6 of the regulating tank, after the sludge is dehydrated, magnesium sulfate enters a magnesium hydroxide recovery tank 8 along with filtrate through a pipeline in a self-flowing way, a dosing pump of a sodium hydroxide dosing unit 19 is started, a sodium hydroxide solution with the mass concentration of 5% is added into the magnesium hydroxide recovery tank 8, the pH value is regulated to 10-11, the medicaments are uniformly mixed under the stirring of a recovery tank stirrer 9, magnesium sulfate reacts with sodium hydroxide to separate out water-insoluble magnesium hydroxide, the magnesium hydroxide is conveyed to a magnesium hydroxide dehydrator 12 through a sludge conveying pump 11 of the recovery tank, the separation of magnesium hydroxide and sodium sulfate is realized through dehydration, and a mud cake (the main component is magnesium hydroxide) is collected in a magnesium hydroxide storage bucket 13 for storage.
When the heavy metal removing agent is required to be added, the magnesium hydroxide in the magnesium hydroxide storage hopper 13 is conveyed into the magnesium hydroxide metering box 15 through the spiral metering conveyor 14, meanwhile, water is fed into the metering box 15, magnesium hydroxide solution with a certain mass concentration is prepared, and the liquid density is monitored through the densitometer 16. When the density of the formulated solution displayed by the densitometer 16 reaches a set value, the magnesium hydroxide solution is transported to the dosing point by the magnesium hydroxide transport pump 17, and is used as a heavy metal remover to remove heavy metal substances in the wastewater.
Because the sludge system is easy to cause pipeline blockage, the sludge pump and pipeline flushing are required after each pump start.
The main substance of the mud cake generated by the sludge dewatering system 3 is calcium sulfate, and the mud cake can be conveyed to a desulfurization system through a transport vehicle to be finally used for producing gypsum.
The foregoing is illustrative of the preferred embodiments of the present utility model and is not to be construed as limiting the claims. The present utility model is not limited to the above embodiments, and the specific structure thereof is allowed to vary. It is intended that all such variations as fall within the scope of the appended claims.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.
Claims (10)
1. The system for recycling the magnesium hydroxide in the basic sludge and serving as the heavy metal removal agent is characterized by comprising a sludge concentration tank (1), a pH adjusting tank (3), a calcium sulfate dehydrator (7), a magnesium hydroxide recycling tank (8), a magnesium hydroxide dehydrator (12) and a magnesium hydroxide metering box (15);
the sludge concentration tank (1) is connected with the pH regulating tank (3), the bottom of the pH regulating tank (3) is connected with the calcium sulfate dehydrator (7), a filtrate outlet of the calcium sulfate dehydrator (7) is connected with the magnesium hydroxide recovery tank (8), the bottom of the magnesium hydroxide recovery tank (8) is connected with the magnesium hydroxide dehydrator (12), and the magnesium hydroxide dehydrator (12) is connected with the magnesium hydroxide metering box (15); the pH adjusting tank (3) is provided with a sulfuric acid dosing interface, and the magnesium hydroxide recycling tank (8) is provided with a sodium hydroxide dosing interface.
2. The system for recovering magnesium hydroxide as heavy metal removing agent from basic sludge according to claim 1, further comprising a sulfuric acid dosing unit (18), wherein the sulfuric acid dosing unit (18) is connected with a sulfuric acid dosing interface provided on the pH adjusting tank (3).
3. The system for recovering magnesium hydroxide as heavy metal removing agent from basic sludge according to claim 1, wherein a regulating tank stirrer (4) and a regulating tank pH meter (5) are provided inside the pH regulating tank (3).
4. The system for recovering magnesium hydroxide from basic sludge for use as a heavy metal remover according to claim 1, further comprising a sodium hydroxide dosing unit (19), wherein the sodium hydroxide dosing unit (19) is connected with a sodium hydroxide dosing interface provided on the magnesium hydroxide recovery tank (8).
5. The system for recovering magnesium hydroxide as heavy metal removing agent from basic sludge according to claim 1, wherein a recovery tank stirrer (9) and a recovery tank pH meter (10) are provided in the magnesium hydroxide recovery tank (8).
6. The system for recovering magnesium hydroxide as heavy metal remover from basic sludge according to claim 1, wherein a densitometer (16) is arranged on the magnesium hydroxide metering box (15).
7. The system for recovering magnesium hydroxide as heavy metal removing agent from basic sludge according to claim 1, wherein the sludge concentration tank (1) is connected with the pH adjusting tank (3) through a concentration tank sludge discharge pump (2).
8. The system for recovering magnesium hydroxide as heavy metal removing agent from basic sludge according to claim 7, wherein the pH adjusting tank (3) is connected with a calcium sulfate dehydrator (7) through an adjusting tank sludge transfer pump (6).
9. The system for recovering magnesium hydroxide as heavy metal removing agent from basic sludge according to claim 8, wherein the magnesium hydroxide recovery tank (8) is connected to a magnesium hydroxide dehydrator (12) through a recovery tank sludge transfer pump (11).
10. The system for recovering magnesium hydroxide as heavy metal removing agent from basic sludge according to claim 9, wherein the concentrating tank sludge pump (2), the regulating tank sludge pump (6), the recovering tank sludge pump (11) and the magnesium hydroxide pump (17) are connected with a flushing device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321532515.7U CN220098829U (en) | 2023-06-15 | 2023-06-15 | System for recovering magnesium hydroxide in basic sludge and using magnesium hydroxide as heavy metal remover |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202321532515.7U CN220098829U (en) | 2023-06-15 | 2023-06-15 | System for recovering magnesium hydroxide in basic sludge and using magnesium hydroxide as heavy metal remover |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220098829U true CN220098829U (en) | 2023-11-28 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202321532515.7U Active CN220098829U (en) | 2023-06-15 | 2023-06-15 | System for recovering magnesium hydroxide in basic sludge and using magnesium hydroxide as heavy metal remover |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220098829U (en) |
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2023
- 2023-06-15 CN CN202321532515.7U patent/CN220098829U/en active Active
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