A phosphorite dressing acidic wastewater precipitant and its use

Abstract

The present application relates to a kind of phosphorite dressing acidic wastewater precipitants, belong to the field of phosphorite dressing.The precipitants are composed of solid carrier and reagent, the solid carrier plays the role of adsorbing precipitate, accelerating sedimentation, accelerating filtration, the reagent plays the role of adjusting the pH value of acidic wastewater and providing the required anion and cation of precipitation.After the acidic wastewater of phosphorite dressing is treated by the precipitants, the sedimentation speed of precipitate increases, the filtration speed increases, and there is no visible solid in the filtrate after filtration.The filtrate after filtration can be used to prepare phosphorite flotation collector, and does not affect the use effect of collector.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of phosphate ore dressing, in particular to a phosphate ore dressing acidic wastewater treatment agent and its application. BACKGROUND

[0002] In the phosphate ore dressing, the reverse flotation of dolomite mineral is the main process flow, and in this operation, a large amount of acidic wastewater is generated. A part of the acidic wastewater can be returned to the grinding and flotation operation for recycling, but there is still a part of the excess acidic wastewater. If the excess acidic wastewater is directly applied to the preparation of the flotation collector, the use effect of the flotation collector will be affected. These acidic wastewater needs to be treated before returning to the collector preparation operation. In the treatment of these acidic wastewater, the precipitation method is often used to remove the cations and anions therein. In the process of generating the precipitate, the precipitate is difficult to settle and filter due to the too small particle size of the precipitate. SUMMARY

[0003] The purpose of the present application is to solve the problem of difficult settlement and filtration of the precipitate in the treatment of acidic wastewater in the phosphate flotation. The present application provides a precipitant specifically used for the acidic wastewater in the phosphate ore dressing, which can enable the precipitate to be adsorbed on the precipitant, and can solve the problem of difficult settlement and filtration of the precipitate.

[0004] The purpose of the present application is achieved by the following technical scheme. The present application is a phosphate ore dressing acidic wastewater precipitant, which is composed of a solid carrier and a medicament. The solid carrier is a carrier for adsorbing the precipitate, accelerating the settlement or accelerating the filtration. The medicament is a medicament for adjusting the pH value of the acidic wastewater and providing the required anions and cations for precipitation.

[0005] The further preferred technical scheme of the above-mentioned phosphate ore dressing acidic wastewater precipitant is that the solid carrier is selected from one or more components of waste stone, phosphogypsum, phosphate ore tailings in any proportion, and the amount of the solid carrier is 1% to 30% of the weight of the acidic wastewater.

[0006] The further preferred technical scheme of the above-mentioned phosphate ore dressing acidic wastewater precipitant is that the medicament is selected from one or more components of sodium hydroxide, potassium hydroxide, calcium oxide, sodium carbonate in any proportion, and the amount of the medicament is 0.05% to 1% of the weight of the acidic wastewater.

[0007] The further preferred technical scheme of the above-mentioned phosphate ore dressing acidic wastewater precipitant is that the solid carrier is a solid particle with a density of 1.5 to 6.0 g / cm 3 , and a particle size of 5 to 0.01 mm.

[0008] The further preferred technical scheme of the phosphorite dressing acidic wastewater precipitant is that the combination of the solid carrier and the reagent is that the reagent is coated on the surface of the solid carrier in solid form, the acidic wastewater reacts with the reagent on the surface of the solid carrier, and the generated precipitate is adsorbed on the surface of the solid carrier.

[0009] The further preferred technical scheme of the phosphorite dressing acidic wastewater precipitant is that the combination of the solid carrier and the reagent is that the reagent is dissolved in an aqueous solution containing 30-80% of the solid carrier, and then the acidic wastewater and the reagent solution are allowed to react near the surface of the solid carrier, and the generated precipitate is adsorbed on the surface of the solid carrier.

[0010] The further preferred technical scheme of the phosphorite dressing acidic wastewater precipitant is that the pH value of the phosphorite dressing acidic wastewater is 6.5-2.0, the content of Ca 2+ in the acidic wastewater is 100-1000 mg / L, the content of Mg 2+ is 150-1500 mg / L, and the content of PO4 3- is 100-6000 mg / L.

[0011] The present application also provides a method for precipitating and treating the phosphorite dressing acidic wastewater, which uses the precipitant according to any one of the above technical schemes for precipitating and treating, and the treatment steps are as follows:

[0012] (1) the precipitant and the phosphorite dressing acidic wastewater are added into a stirring barrel for stirring and reaction;

[0013] (2) the generated precipitate and the solid carrier are transported together from the stirring barrel to a thickener;

[0014] (3) the supernatant on the upper layer of the thickener is directly returned to the preparation of the phosphorite dressing collecting agent, the filtrate after the solid on the lower layer of the thickener is filtered is returned to the preparation of the phosphorite dressing collecting agent, and the solid is stored for treatment.

[0015] The use of the phosphorite dressing acidic wastewater precipitant is to use the precipitant to treat the phosphorite dressing acidic wastewater.

[0016] Compared with the existing phosphorite dressing acidic wastewater treatment technology, the present application has the following beneficial effects: the present application uses the solid carrier to adsorb the fine-grained precipitate generated in the treatment of the acidic wastewater, which can accelerate the settling and filtering speed of the precipitate in the treatment process. The method is simple and easy to implement, has low cost, and has a wide source of solid carriers, strong adaptability, and high application value. DETAILED DESCRIPTION

[0017] The specific technical schemes of the present application are further described below to facilitate those skilled in the art to further understand the present application without limiting the rights thereof.

[0018] Example 1, a phosphorite dressing acidic wastewater precipitant, the precipitant is composed of a solid carrier and a medicament, the solid carrier is a carrier for adsorbing precipitates, accelerating sedimentation or accelerating filtration, the medicament is a medicament for adjusting the pH value of the acidic wastewater and providing the required anion and cation for precipitation. The solid carrier is selected from one of waste rock, phosphogypsum, phosphorite tailings, the amount of the solid carrier is 10% of the weight of the acidic wastewater. The medicament is selected from one of sodium hydroxide, potassium hydroxide, calcium oxide, sodium carbonate, the amount of the medicament is 0.25% of the weight of the acidic wastewater. The solid carrier is a solid particle with a density of 2.0 g / cm 3 , a particle size of 1-0.5 mm.

[0019] The combination of the solid carrier and the medicament is that the medicament is coated on the surface of the solid carrier in a solid form, the acidic wastewater reacts with the medicament on the surface of the solid carrier, the generated precipitates are adsorbed on the surface of the solid carrier, or the medicament is dissolved in an aqueous solution containing 30% of the solid carrier, then the acidic wastewater and the medicament solution are allowed to react near the surface of the solid carrier, and the generated precipitates are adsorbed on the surface of the solid carrier.

[0020] The treatment steps are:

[0021] (1) the precipitant and the phosphorite dressing acidic wastewater are added into a stirring barrel for stirring reaction;

[0022] (2) the generated precipitates and the solid carrier are transported together from the stirring barrel to a thickener;

[0023] (3) the supernatant on the upper layer of the thickener is directly returned to the preparation of the phosphorite dressing collector for use, the filtrate after the solid on the lower layer of the thickener is filtered is returned to the preparation of the phosphorite dressing collector for use, and the solid is stored for treatment.

[0024] Example 2, a phosphorite dressing acidic wastewater precipitant, the precipitant is composed of a solid carrier and a medicament, the solid carrier is a carrier for adsorbing precipitates, accelerating sedimentation or accelerating filtration, the medicament is a medicament for adjusting the pH value of the acidic wastewater and providing the required anion and cation for precipitation.

[0025] The solid carrier is selected from one or more components in any proportion of a combination of waste rock, phosphogypsum, phosphorite tailings, the amount of the solid carrier is 30% of the weight of the acidic wastewater. The medicament is selected from one or more components in any proportion of a combination of sodium hydroxide, potassium hydroxide, calcium oxide, sodium carbonate, the amount of the medicament is 1% of the weight of the acidic wastewater. The solid carrier is a solid particle with a density of 1.5 g / cm 3 , a particle size of 5-0.01 mm. The pH value of the phosphorite dressing acidic wastewater is 6.5-2.0, the content of Ca 2+ in the acidic wastewater is 100-1000 mg / L, the content of Mg 2+PO4 3- PO4

[0026] The precipitant is used for precipitation treatment, and the treatment step is:

[0027] (1) The precipitant and the phosphorite beneficiation acidic wastewater are added into a stirring barrel for stirring reaction;

[0028] (2) The generated precipitate and the solid carrier are transported from the stirring barrel to a thickener;

[0029] (3) The supernatant on the thickener is directly returned to the phosphorite beneficiation collector preparation for use, the filtrate after the solid is filtered is returned to the phosphorite beneficiation collector preparation for use, and the solid is stored.

[0030] Example 3: Experiment one of the phosphorite beneficiation acidic wastewater precipitation treatment method

[0031] The phosphorite beneficiation acidic wastewater has a pH value of 5.24, Ca 2+ 345.6 mg / L, Mg 2+ 1247.6 mg / L,

[0032] PO4 3- 5197.0 mg / L, quantitative NaOH solution is sprayed on the solid phosphorite tailings, and after drying, the NaOH solution is used as a precipitant, then the phosphorite beneficiation acidic wastewater and the precipitant are reacted in a stirring barrel, when the pH value of the acidic wastewater is adjusted to alkaline 8.5, the generated fine-grained precipitate is adsorbed by the phosphorite tailings, the particle size of the phosphorite tailings is 1-0.01 mm, the specific gravity is 2.83 g / cm 3 , the settling speed of the generated precipitate is 48 cm / h, and there is no visible solid in the filtrate after filtration.

[0033] Example 4: Experiment two of the phosphorite beneficiation acidic wastewater precipitation treatment method

[0034] The phosphorite beneficiation acidic wastewater has a pH value of 5.24, Ca 2+ 345.6 mg / L, Mg 2+ 1247.6 mg / L,

[0035] PO4 3- 5197.0 mg / L, quantitative NaOH solution is sprayed on the solid waste rock, and after drying, the NaOH solution is used as a precipitant, then the phosphorite beneficiation acidic wastewater and the precipitant are reacted in a stirring barrel, when the pH value of the acidic wastewater is adjusted to alkaline 8.5, the generated fine-grained precipitate is adsorbed by the phosphorite tailings, the particle size of the phosphorite tailings is 1-0.01 mm, the specific gravity is 2.83 g / cm 3 , the settling speed of the generated precipitate is 56 cm / h, and there is no visible solid in the filtrate after filtration.

[0036] Example 5: The second experiment of the precipitation treatment method of the phosphorite dressing acidic wastewater

[0037] The phosphorite dressing acidic wastewater, pH value 5.24, Ca 2+ 345.6 mg / L, Mg 2+ 1247.6 mg / L,

[0038] PO4 3- 5197.0 mg / L, the quantitative KOH solution is sprayed on the solid phosphogypsum, and after drying, it is used as a precipitant, then the phosphorite dressing acidic wastewater is reacted with the precipitant in a stirring barrel, the pH value of the acidic wastewater is adjusted to alkaline 8.5, the generated fine particle precipitate is adsorbed by the phosphogypsum, the phosphogypsum particle size is 1-0.01 mm, the specific gravity is 3.12 g / cm 3 , the generated precipitate settling velocity is 54 cm / h, and there is no visible solid in the filtrate after filtration.

[0039] Example 6: The fourth experiment of the precipitation treatment method of the phosphorite dressing acidic wastewater

[0040] The phosphorite dressing acidic wastewater, pH value 5.24, Ca 2+ 345.6 mg / L, Mg 2+ 1247.6 mg / L,

[0041] PO4 3- 5197.0 mg / L, the quantitative KOH solution is sprayed on the solid phosphogypsum, and after drying, it is used as a precipitant, then the phosphorite dressing acidic wastewater is reacted with the precipitant in a stirring barrel, the pH value of the acidic wastewater is adjusted to alkaline 8.5, the generated fine particle precipitate is adsorbed by the phosphogypsum, the phosphogypsum particle size is 1-0.01 mm, the specific gravity is 3.12 g / cm 3 , the generated precipitate settling velocity is 54 cm / h, and there is no visible solid in the filtrate after filtration.

[0042] Example 7: The fifth experiment of the precipitation treatment method of the phosphorite dressing acidic wastewater

[0043] The phosphorite dressing acidic wastewater, pH value 5.24, Ca 2+ 345.6 mg / L, Mg 2+ 1247.6 mg / L,

[0044] PO4 3-5197.0 mg / L, the quantitative CaO is dissolved in the water solution with the content of 60% of the phosphate tailings, used as the precipitant, then the phosphate dressing acidic wastewater is reacted with the precipitant in the stirring barrel, the pH value of the acidic wastewater is adjusted to the alkalinity 9.2, the generated fine particle precipitate is adsorbed by the phosphate tailings, the particle size of the phosphate tailings is 1-0.01 mm, the specific gravity is 2.83 g / cm 3 , the generated precipitate has the settling speed of 52 cm / h, and no visible solid is in the filtrate after filtration.

[0045] Example 8: the sixth experiment of the precipitate treatment method of the phosphate dressing acidic wastewater

[0046] The phosphate dressing acidic wastewater has the pH value 5.24, Ca 2+ 345.6 mg / L, Mg 2+ 1247.6 mg / L,

[0047] PO4 3- 5197.0 mg / L, the quantitative NaCO3 is dissolved in the water solution with the content of 50% of the phosphate tailings, used as the precipitant, then the phosphate dressing acidic wastewater is reacted with the precipitant in the stirring barrel, the pH value of the acidic wastewater is adjusted to the alkalinity 8.7, the generated fine particle precipitate is adsorbed by the phosphate tailings, the particle size of the phosphate tailings is 1-0.01 mm, the specific gravity is 2.83 g / cm 3 , the generated precipitate has the settling speed of 52 cm / h, and no visible solid is in the filtrate after filtration.

[0048] Example 9: the seventh experiment of the precipitate treatment method of the phosphate dressing acidic wastewater

[0049] The phosphate dressing acidic wastewater has the pH value 5.24, Ca 2+ 345.6 mg / L, Mg 2+ 1247.6 mg / L,

[0050] PO4 3- 5197.0 mg / L, the quantitative NaOH is dissolved in the water solution with the content of 40% of the phosphate tailings, used as the precipitant, then the phosphate dressing acidic wastewater is reacted with the precipitant in the stirring barrel, the pH value of the acidic wastewater is adjusted to the alkalinity 8.7, the generated fine particle precipitate is adsorbed by the phosphate tailings, the particle size of the phosphate tailings is 1-0.01 mm, the specific gravity is 2.83 g / cm 3 , the generated precipitate has the settling speed of 52 cm / h, and no visible solid is in the filtrate after filtration.

[0051] The filtered filtrate is used to prepare a phosphate ore flotation collector, and beneficiation evaluation tests are carried out. The test results show that compared with using clean water to prepare the phosphate ore flotation collector, the test effect of using the filtered filtrate to prepare the phosphate ore flotation collector is the same. The treated phosphate ore beneficiation acidic wastewater can be used to prepare the phosphate ore flotation collector.

[0052] Comparative Example 1: Precipitation treatment method of phosphate ore beneficiation acidic wastewater

[0053] Phosphate ore beneficiation acidic wastewater, pH value 5.24, Ca 2+ 345.6 mg / L, Mg 2+ 1247.6 mg / L,

[0054] PO4 3- 5197.0 mg / L, when the pH value is directly adjusted to alkaline 8.7 by NaOH, the settling speed of the generated precipitate is 0.125 cm / h, the filtrate after filtration is turbid, and the precipitate penetrates the filter paper.

Claims

1. A precipitant for acidic wastewater from phosphate rock beneficiation, characterized in that, The precipitant consists of a solid carrier and a reagent. The solid carrier is used to adsorb precipitates, accelerate sedimentation, or accelerate filtration. The reagent is used to adjust the pH value of acidic wastewater and provide the anions and cations required for precipitation. The solid carrier is selected from one or more components of waste rock, phosphogypsum, and phosphate rock tailings in any proportion, and the amount of solid carrier used is 1% to 30% of the weight of acidic wastewater. The combination of solid carrier and reagent is as follows: the reagent is coated on the surface of solid carrier in solid form, acidic wastewater reacts with the reagent on the surface of solid carrier, and the resulting precipitate is adsorbed on the surface of solid carrier. Alternatively, the combination of the solid carrier and the reagent can be as follows: the reagent is dissolved in an aqueous solution with a solid carrier content of 30%-80%, and then the acidic wastewater and the reagent solution react near the surface of the solid carrier, and the resulting precipitate is adsorbed by the surface of the solid carrier.

2. The precipitant for acidic wastewater from phosphate rock beneficiation according to claim 1, characterized in that: The reagent is selected from one or more components of sodium hydroxide, potassium hydroxide, calcium oxide, and sodium carbonate in any proportion, and the dosage of the reagent is 0.05% to 1% of the weight of the acidic wastewater.

3. The precipitant for acidic wastewater from phosphate rock beneficiation according to claim 1, characterized in that: The solid carrier has a density of 1.5–6.0 g / cm³. 3 Solid particles with a particle size of 5-0.01 mm.

4. A precipitant for acidic wastewater from phosphate rock beneficiation according to any one of claims 1-3, characterized in that: The pH value of acidic wastewater from phosphate rock beneficiation is 6.5-2.0, and the calcium content in the acidic wastewater is... 2+ The content is 100-1000 mg / L, Mg 2+ The content is 150-1500 mg / L, PO4 3 The content is 100-6000 mg / L.

5. A method for precipitation treatment of acidic wastewater from phosphate rock beneficiation, characterized in that: This method uses the precipitant according to any one of claims 1-4 for precipitation treatment, and the treatment steps are as follows: (1) Add the precipitant and acidic wastewater from phosphate rock beneficiation into a mixing tank and stir to react; (2) The generated precipitate and solid carrier are transported together from the mixing tank to the thickener; (3) The clear liquid in the upper layer of the thickener is directly returned to the preparation of phosphate rock beneficiation collector, and the filtrate after the solids in the lower layer of the thickener are returned to the preparation of phosphate rock beneficiation collector. The solids are then stored and treated.

6. The application of a precipitant for acidic wastewater from phosphate rock beneficiation, characterized in that, The intended use is to use the precipitant described in any one of claims 1-3 to treat acidic wastewater from phosphate rock beneficiation.