Strong brine treatment system

Abstract

The utility model discloses a strong brine treatment system which comprises an adjusting tank, a reaction tank, a microfiltration membrane separator, a decarburization tower, a triple-effect evaporator, a sand filter, a thickener, a centrifugal machine and a drying machine. The device has the advantages that sodium ions, calcium ions and chloride ions in the strong brine can be effectively recovered, only a small amount of medicament is used in the silicon removal stage, the medicament use can be effectively reduced, the medicament cost is reduced, the calcium ions are recovered in the form of calcium chloride, the sludge amount is reduced, the sludge treatment cost can be further reduced, and the energy consumption is reduced. And the produced saturated calcium chloride solution can generate economic benefits, so that the treatment cost of the strong brine can be effectively reduced, the economic benefits can be improved, and meanwhile, the utilization rate of effective components can be improved.

Description

Technical Field:

[0001] The utility model relates to a metal ore wastewater treatment system, specifically to a concentrated brine treatment system. Background Art:

[0002] The mining concentrated brine of metal ore contains substances such as chloride ions, calcium ions, sodium ions, bicarbonate radicals, soluble silica, and magnesium ions. The traditional treatment method is to add lime, sodium carbonate, PFS, and PAM to remove hardness in the form of calcium carbonate and magnesium hydroxide, remove calcium ions and magnesium ions in the form of sludge, and then further treat the concentrated brine to produce sodium salt products. The above treatment process consumes a large amount of chemicals, and the chemical cost is relatively high. Moreover, the separated sludge needs to be entrusted to a professional qualified unit for treatment, which will increase a part of the sludge disposal cost. And, the contents of chloride ions, calcium ions, and sodium ions are relatively high, with the chloride ion concentration being 35467 mg / L, the calcium ion concentration being 10500 mg / L, and the sodium ion concentration being 9800 mg / L. The above treatment can only recover chloride ions and sodium ions, while calcium ions are discharged as solid waste, reducing the utilization rate of effective components. Content of the Utility Model:

[0003] The purpose of the utility model is to provide a concentrated brine treatment system.

[0004] The utility model is implemented by the following technical solutions: A concentrated brine treatment system includes an adjustment tank, a reaction tank, a microfiltration membrane separator, a decarbonization tower, a triple-effect evaporator, a sand filter, a thickener, a centrifuge, and a dryer. The upper part of the adjustment tank is connected with a water inlet pipe and a sodium hydroxide feeding pipe. The outlet of the adjustment tank is connected with the inlet of the reaction tank. The upper part of the reaction tank is connected with a sodium aluminate feeding pipe and a flocculant feeding pipe. The outlet of the reaction tank is connected with the inlet of the microfiltration membrane separator. The liquid phase outlet of the microfiltration membrane separator is connected with the inlet of the decarbonization tower. The side part of the decarbonization tower is connected with a blast pipe. The outlet of the decarbonization tower is connected with the inlet of the triple-effect evaporator. The mother liquor outlet of the triple-effect evaporator is connected with the inlet of the sand filter. The outlet of the sand filter is connected with the inlet of a calcium chloride storage tank. The crystal slurry outlet of the triple-effect evaporator is connected with the inlet of the thickener. The solid phase outlet of the thickener is connected with the inlet of the centrifuge. The solid phase outlet of the centrifuge is connected with the inlet of the dryer. The outlet of the dryer is connected with a sodium chloride discharge pipe.

[0005] Further, the solid phase outlet of the microfiltration membrane separator is connected with the inlet of a sludge thickening tank. The solid phase outlet of the sludge thickening tank is connected with the inlet of a filter press.

[0006] Further, the liquid phase outlet of the sludge thickening tank and the liquid phase outlet of the filter press are both connected with the inlet of the reaction tank.

[0007] Further, the liquid phase outlet of the thickener and the liquid phase outlet of the centrifuge are both connected to the inlet of the triple-effect evaporator.

[0008] Advantages of the present utility model: In the present utility model, sodium hydroxide is first put into the adjustment tank, then sodium aluminate and a flocculant are added to the reaction tank, and then separation is carried out through a microfiltration membrane separator to remove total silicon in the concentrated brine; then carbon dioxide and bicarbonate ions soluble in the solution are removed in the decarbonization tower, and finally sodium chloride is separated by triple-effect evaporation. The remaining mother liquor is a saturated calcium chloride solution, which can be used for industrial production. The present utility model can effectively recover sodium ions, calcium ions and chloride ions in the concentrated brine, and only a small amount of medicaments are used in the silicon removal stage, which can effectively reduce the use of medicaments and reduce the medicament cost. Moreover, calcium ions are recovered in the form of calcium chloride, reducing the amount of sludge, and thus the sludge treatment cost can be reduced. In addition, the produced saturated calcium chloride solution can generate economic benefits. Therefore, the present utility model can effectively reduce the treatment cost of concentrated brine, improve economic benefits, and at the same time improve the utilization rate of effective components. Brief description of the drawings:

[0009] Figure 1 It is a schematic diagram of the overall structure of this embodiment.

[0010] Adjustment tank 1, reaction tank 2, microfiltration membrane separator 3, decarbonization tower 4, triple-effect evaporator 5, sand filter 6, thickener 7, centrifuge 8, dryer 9, water inlet pipe 10, sodium hydroxide feed pipe 11, sodium aluminate feed pipe 12, flocculant feed pipe 13, air duct 14, calcium chloride storage tank 15, sodium chloride discharge pipe 16, sludge thickening tank 17, filter press 18. Specific implementation manners:

[0011] In the description of the present utility model, it should be noted that when terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. appear, the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present utility model. In addition, when terms such as "first", "second", "third" appear, they are only for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0012] Such as Figure 1As shown in the figure, a concentrated brine treatment system includes an adjustment tank 1, a reaction tank 2, a microfiltration membrane separator 3, a decarbonization tower 4, a triple-effect evaporator 5, a sand filter 6, a thickener 7, a centrifuge 8, and a dryer 9. The upper part of the adjustment tank 1 is connected to a water inlet pipe 10 and a sodium hydroxide feeding pipe 11. The outlet of the adjustment tank 1 is connected to the inlet of the reaction tank 2. The upper part of the reaction tank 2 is connected to a sodium aluminate feeding pipe 12 and a flocculant feeding pipe 13. The outlet of the reaction tank 2 is connected to the inlet of the microfiltration membrane separator 3. The solid-phase outlet of the microfiltration membrane separator 3 is connected to the inlet of the sludge thickening tank 17. The solid-phase outlet of the sludge thickening tank 17 is connected to the inlet of the filter press 18. The liquid-phase outlets of both the sludge thickening tank 17 and the filter press 18 are connected to the inlet of the reaction tank 2.

[0013] The liquid-phase outlet of the microfiltration membrane separator 3 is connected to the inlet of the decarbonization tower 4. The side of the decarbonization tower 4 is connected to an air blowing pipe 14. The outlet of the decarbonization tower 4 is connected to the inlet of the triple-effect evaporator 5. The mother liquor outlet of the triple-effect evaporator 5 is connected to the inlet of the sand filter 6. The outlet of the sand filter 6 is connected to the inlet of the calcium chloride storage tank 15. The crystal slurry outlet of the triple-effect evaporator 5 is connected to the inlet of the thickener 7. The solid-phase outlet of the thickener 7 is connected to the inlet of the centrifuge 8. The solid-phase outlet of the centrifuge 8 is connected to the inlet of the dryer 9. The outlet of the dryer 9 is connected to a sodium chloride discharge pipe 16. The liquid-phase outlets of both the thickener 7 and the centrifuge 8 are connected to the inlet of the triple-effect evaporator 5.

[0014] Treatment process:

[0015] S1: Feed concentrated brine into the adjustment tank 1 through the water inlet pipe 10 and add sodium hydroxide into the adjustment tank 1 through the sodium hydroxide feeding pipe 11 to adjust the pH to 8 - 8.5. And the following reaction occurs:

[0016] 2NaOH + SiO2 = Na2SiO3 + H2O

[0017] S2: Feed the concentrated brine discharged from the adjustment tank 1 into the reaction tank 2. First, add sodium aluminate through the sodium aluminate feeding pipe 12. Sodium aluminate reacts with sodium silicate to form Na2Al2Si2O8 precipitate. Then add a flocculant to flocculate the precipitate.

[0018] S3: Feed the liquid discharged from the reaction tank 2 to the microfiltration membrane separator 3 for solid-liquid separation. The separated sludge is sent to the sludge thickening tank 17 for further thickening treatment. The sludge discharged from the sludge thickening tank 17 is sent to the filter press 18 for filtration and then discharged. The liquid phases discharged from both the sludge thickening tank 17 and the filter press 18 are sent back to the reaction tank 2 for circulation treatment.

[0019] S4: Feed the liquid discharged from the microfiltration membrane separator 3 into the decarbonization tower 4 and blow air through the air blowing pipe 14. The bicarbonate ions in the concentrated brine are easily combined with H in the water +Combined into H2O and CO2, and the CO2 dissolved in the raw water is easy to precipitate and remove under the condition of blowing air;

[0020] S5: The concentrated brine discharged from the decarbonization tower 4 is sent to the triple-effect evaporator 5 for evaporation and concentration to precipitate sodium chloride. The crystal slurry discharged from the triple-effect evaporator 5 passes through the thickener 7, centrifuge 8, and dryer 9 in sequence for concentration, solid-liquid separation, and drying treatment. The obtained sodium chloride is discharged from the system through the sodium chloride discharge pipe, and the liquid phase discharged from the thickener 7 and centrifuge 8 is sent back to the triple-effect evaporator 5 for recycling treatment;

[0021] S6: The mother liquor discharged from the triple-effect evaporator 5 is a saturated calcium chloride solution. First, it is filtered by the sand filter 6 to remove impurities and then sent to the calcium chloride storage tank 15 for collection. The saturated calcium chloride solution collected in the calcium chloride storage tank 15 can be used in industrial production, such as for washing to remove excess ethanol and removing ether.

[0022] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A concentrated brine treatment system, characterized in that, It includes an adjustment tank, a reaction tank, a microfiltration membrane separator, a decarbonization tower, a triple-effect evaporator, a sand filter, a thickener, a centrifuge and a dryer. The upper part of the adjustment tank is connected with a water inlet pipe and a sodium hydroxide feeding pipe. The outlet of the adjustment tank is connected with the inlet of the reaction tank. The upper part of the reaction tank is connected with a sodium aluminate feeding pipe and a flocculant feeding pipe. The outlet of the reaction tank is connected with the inlet of the microfiltration membrane separator. The liquid phase outlet of the microfiltration membrane separator is connected with the inlet of the decarbonization tower. The side part of the decarbonization tower is connected with an air blowing pipe. The outlet of the decarbonization tower is connected with the inlet of the triple-effect evaporator. The mother liquor outlet of the triple-effect evaporator is connected with the inlet of the sand filter. The outlet of the sand filter is connected with the inlet of a calcium chloride storage tank. The crystal slurry outlet of the triple-effect evaporator is connected with the inlet of the thickener. The solid phase outlet of the thickener is connected with the inlet of the centrifuge. The solid phase outlet of the centrifuge is connected with the inlet of the dryer. The outlet of the dryer is connected with a sodium chloride discharge pipe.

2. The brine treatment system according to claim 1, characterized in that, The solid phase outlet of the microfiltration membrane separator is connected with the inlet of a sludge thickening tank. The solid phase outlet of the sludge thickening tank is connected with the inlet of a filter press.

3. The brine treatment system according to claim 2, wherein, The liquid phase outlet of the sludge thickening tank and the liquid phase outlet of the filter press are both connected with the inlet of the reaction tank.

4. A concentrated brine treatment system according to any one of claims 1 to 3, characterized in that, The liquid phase outlet of the thickener and the liquid phase outlet of the centrifuge are both connected with the inlet of the triple-effect evaporator.

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