CN107628632B - Method for preparing flocculant polyaluminium chloride by using fly ash - Google Patents
Method for preparing flocculant polyaluminium chloride by using fly ash Download PDFInfo
- Publication number
- CN107628632B CN107628632B CN201710909253.4A CN201710909253A CN107628632B CN 107628632 B CN107628632 B CN 107628632B CN 201710909253 A CN201710909253 A CN 201710909253A CN 107628632 B CN107628632 B CN 107628632B
- Authority
- CN
- China
- Prior art keywords
- fly ash
- acid
- sodium
- chloride
- solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Processing Of Solid Wastes (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
Abstract
The invention belongs to the technical field of flocculant production, and particularly relates to a method for preparing flocculant polyaluminium chloride by using fly ash. The method for preparing the flocculant polyaluminium chloride by using the fly ash comprises the following steps: grinding and sieving the fly ash, and carrying out ultrasonic treatment on the fly ash by using an alkali solution; mixing the fly ash subjected to alkali treatment, a composite sodium additive and water, and performing microwave activation to obtain pre-activated fly ash; calcining and activating the pre-activated fly ash at a high temperature to obtain secondary activated fly ash; acid leaching and high-temperature and high-pressure acid leaching are carried out on the secondary activated fly ash, and then the basicity is adjusted by the calcium aluminate mineral powder to obtain the polyaluminium chloride. The method has the advantages of simple operation and low cost, is suitable for industrial production, takes the fly ash as the raw material, changes waste into valuable, reduces the production cost, and avoids the environmental pollution caused by the waste of the fly ash solid.
Description
Technical Field
The invention belongs to the technical field of flocculant production, and particularly relates to a method for preparing flocculant polyaluminium chloride by using fly ash.
Background
The fly ash is solid waste generated after coal combustion, and the main chemical component of the fly ash mainly comprises Al2O3、Fe2O3、SiO2、CaO、K2O, and the like. Wherein, Al2O3About 15 to 40% of SiO2The content of the fly ash is about 34-66%, the fly ash is a typical aluminosilicate mineral, and in addition, the fly ash contains trace elements such as Ge, Ga, U, Ni, Pt and the like. Most of the fly ash is grey white to black, so that the carbon content can be seen. The fly ash particles have the particle size of 0.5-300 mu m, are porous materials, have large specific surface area and good adsorption activity.
About 98% of coal is utilized in China through a combustion mode, a large amount of fly ash is generated in the coal burning process, and the fly ash accounts for 10-40% of the mass of raw coal. About 1 million tons of fly ash are accumulated in China every year, the accumulated accumulation amount exceeds 27 million tons, and the fly ash becomes one of the accumulated accumulation amount and the most industrial waste in China. The generation and treatment of a large amount of fly ash not only causes pollution to air, soil and water resources, but also occupies a large amount of open land (including cultivated land), and seriously affects the living environment of people, so that the clean utilization of coal and the active treatment of fly ash become one of important contents of energy strategies in China.
At present, the comprehensive utilization approach of the fly ash is mainly in the aspects of building materials, construction, agriculture, environmental protection and the like. However, the utilization mode of the fly ash is single, the problem of mass stockpiling of the fly ash is difficult to fundamentally solve, the comprehensive utilization rate is low, and the fly ash cannot be effectively applied. Therefore, the increase of the resource utilization of the fly ash has great significance for reducing the storage of the fly ash and improving the effective utilization of resources.
Polyaluminum Chloride (PAC) is a water-soluble inorganic polymeric flocculant between aluminum Chloride and aluminum hydroxide, has the advantages of fast flocculating body forming, rapid sedimentation, good coagulation effect, wide pH value adaptation, strong adaptability, wide application and the like, and is widely applied to the aspects of water purification, wastewater treatment, papermaking sizing, casting forming and the like. The fly ash contains a large amount of Al source required by PAC synthesis, is low in price, and can be theoretically used as an ideal raw material for preparing PAC.
However, fly ash exists mainly in the form of aluminosilicate glass, mullite, tricalcium aluminate, melilite, sodalite, spinel ferrite and the like, has very high polymerization degree, and is difficult to utilize. Therefore, the fly ash needs to be activated to extract useful substances such as aluminum, iron and the like from the fly ash for utilization. The activation of the fly ash is divided into physical activation and chemical activation, wherein the physical activation mainly achieves the purpose of activation by utilizing a mechanical grinding and microwave dissolution assisting method; the chemical activation mainly comprises a lime sintering method, an auxiliary agent calcining method, a method for dissolving the fly ash in an acid system by fluoride, and the like. Research results show that physical activation is simple to operate, but mechanical grinding time is long, and the extraction rate of aluminum and iron is low. The limestone sintering method in chemical activation has complex process and good fluoride dissolution assisting effect, but is limited due to the pollution of fluorine ions.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a method for preparing flocculant polyaluminium chloride by using fly ash.
The purpose of the invention is realized by the following technical scheme:
a method for preparing flocculant polyaluminium chloride by using fly ash comprises the following steps:
(1) grinding and sieving the fly ash, then carrying out ultrasonic treatment for 5-10 min at 40-60 ℃ by using an alkali solution, carrying out solid-liquid separation, washing to be neutral, and drying to obtain alkali-treated fly ash;
(2) mixing the coal ash subjected to alkali treatment in the step (1), a composite sodium additive and water, performing microwave activation at 600-800W for 5-10 min, drying, crushing and sieving to obtain pre-activated coal ash;
(3) calcining and activating the pre-activated fly ash prepared in the step (2) for 1-2 hours at 750-900 ℃, crushing and sieving to obtain secondary activated fly ash;
(4) performing acid leaching on the secondary activated fly ash prepared in the step (3), and performing solid-liquid separation to obtain an aluminum salt solution; adjusting the pH value of the aluminum salt solution to be not less than 12, and carrying out solid-liquid separation; adjusting the pH value of the solution to 5-8, and carrying out solid-liquid separation to obtain aluminum hydroxide and filtrate; drying the filtrate to obtain a mixture of sodium sulfate and sodium chloride, which can be used as an auxiliary agent for activating the fly ash;
(5) dissolving the aluminum hydroxide prepared in the step (4) in acid at high temperature and high pressure, and then adjusting the basicity by using calcium aluminate powder to obtain polyaluminium chloride;
the alkali solution in the step (1) is preferably at least one of a sodium hydroxide solution and a sodium carbonate solution, wherein the hydroxide ion concentration of the alkali solution is preferably 1.5-3 mol/L;
the power of the ultrasound in the step (1) is preferably 300-400W;
the compound sodium assistant in the step (2) is preferably a mixture of sodium carbonate, sodium chloride and sodium sulfate;
the mass ratio of the sodium carbonate to the sodium chloride to the sodium sulfate is preferably 4: (0.5-1.5): 1;
the mass ratio of the fly ash, the composite sodium assistant and the water in the step (2) is preferably 1: (1-1.5): (2-4);
the calcination activation condition in the step (3) is preferably calcination activation for 1.2-1.5 h at 800-850 ℃;
the acid leaching reagent in the step (4) is preferably mixed acid with the pH value of 1-2.5;
the mixed acid is a mixture of hydrochloric acid and sulfuric acid;
the mass ratio of the hydrochloric acid to the sulfuric acid is preferably (0.5-1.5): 1;
the solid-to-liquid ratio of the secondary activated fly ash to the acid leaching reagent in the step (4) is preferably 1: (3-6);
the preferred temperature of acid leaching in the step (4) is 90-110 ℃; the time for acid leaching is preferably 1-2 h;
the acid solvent dissolved in the high-temperature and high-pressure acid in the step (5) is preferably hydrochloric acid;
the mass fraction of the hydrochloric acid is preferably 20-25%;
the preferable conditions of high-temperature and high-pressure acid dissolution in the step (5) are that the temperature is 110-140 ℃, the pressure is 0.2-0.4 MPa, and the reaction time is 2.5-4 h;
the principle of the invention is as follows:
the surface modification method adopts ultrasound and alkali solution to carry out surface modification on the fly ash, wherein the ultrasound treatment can rapidly generate a mechanical crushing effect on the fly ash, so that the internal fracture surface of the fly ash is increased, pore blocking impurities are eliminated, the cavitation effect of the ultrasonic treatment plays an auxiliary role in the alkali solution treatment, under the ultrasound condition, the alkali solution further modifies and activates the fly ash, silicon dioxide on the surfaces of fly ash particles can be chemically dissociated to generate variable charges, hard shells on the surfaces of the fly ash particles can be damaged, the specific surface area of the hard shells is increased, further leaching of aluminum oxide is facilitated, and volatile components are removed. Mixing the fly ash subjected to ultrasonic pretreatment by using an aqueous alkali with a composite sodium assistant, and respectively performing microwave activation and calcination strengthening activation, wherein the leaching rate of alumina reaches more than 96%, wherein the composite sodium assistant consisting of sodium carbonate, sodium sulfate and sodium chloride has a remarkable coordination promotion effect, and nepheline formed in the sintering process respectively reacts with hydrochloric acid and sulfuric acid in the acid leaching process to obtain aluminum salt, silica gel precipitate, sodium sulfate and sodium chloride, and the silica gel precipitate is subjected to solid-liquid separation to remove active silica which is difficult to dissolve in acid; further adjusting the pH value of the solution to be not less than 12, carrying out solid-liquid separation, and removing residual Fe3+、Fe2+、Mg2+、Ca2+And (3) carrying out impurity ion treatment, adjusting the pH value of the solution to 5-8 again, carrying out suction filtration to obtain aluminum hydroxide, wherein the filtrate is sodium sulfate and sodium chloride, and can be further used for activating the fly ash by using a sodium assistant.
Compared with the prior art, the invention has the following advantages and effects:
(1) according to the invention, the coal ash is subjected to ultrasonic pretreatment by using the alkali solution, so that volatile components and part of impurity ions of the coal ash can be effectively removed, the specific surface area of the coal ash is increased, the form of the coal ash is changed, the coal ash is subjected to primary modification and activation, and further leaching of alumina is facilitated.
(2) The invention organically combines microwave activation and calcination activation, and can make SiO in the fly ash2、Al2O3The activity of the substances is obviously increased, the breakage of Si-Al bonds is promoted, and the Al is accelerated2O3The leaching speed and the leaching rate of the alumina reach over 96 percent.
(3) The invention adopts the composite sodium additive to activate the fly ash, has obvious coordination and promotion effects, can obviously improve the reaction activity of the fly ash, and can recycle the sodium sulfate and the sodium chloride.
(4) The method is simple to operate, low in cost and suitable for industrial production.
(5) The invention takes the fly ash as the raw material, changes waste into valuable, reduces the production cost and avoids the pollution of the waste of the fly ash solid to the environment.
Detailed Description
The present invention will be described in further detail with reference to examples, but the embodiments of the present invention are not limited thereto.
The fly ash in the examples comes from a power plant in inner Mongolia;
example 1
A method for preparing flocculant polyaluminium chloride by using fly ash comprises the following steps:
(1) grinding and sieving the fly ash, then carrying out ultrasonic treatment on the fly ash for 8min at 50 ℃ and 350W by using a sodium hydroxide solution (the concentration of hydroxide ions is 2mol/L), carrying out solid-liquid separation, washing to be neutral, and drying to obtain the alkali-treated fly ash;
(2) mixing the fly ash subjected to alkali treatment in the step (1), a composite sodium additive and water, performing 700W microwave activation for 8min, drying, crushing and sieving to obtain pre-activated fly ash; the composite sodium additive is a mixture of sodium carbonate, sodium chloride and sodium sulfate, and the mass ratio of the sodium carbonate to the sodium chloride to the sodium sulfate is 4: 1: 1; the mass ratio of the fly ash to the composite sodium assistant to the water is 1: 1.2: 3;
(3) calcining and activating the pre-activated fly ash prepared in the step (2) for 1.3h at 820 ℃, crushing and sieving to obtain secondary activated fly ash;
(4) acid-leaching the secondary activated fly ash prepared in the step (3) in mixed acid with the pH value of 2 (the mass ratio of hydrochloric acid to sulfuric acid is 1: 1) at 106 ℃ for 1.5h, and carrying out solid-liquid separation to obtain an aluminum salt solution; adjusting the pH value of the aluminum salt solution to 13, carrying out solid-liquid separation, and removing Fe3+、Fe2+、Mg2+、Ca2+Plasma impurity ions; adjusting the pH value of the solution to 7, and carrying out solid-liquid separation to obtain aluminum hydroxide and filtrate; drying the filtrate to obtain a mixture of sodium sulfate and sodium chloride, which can be used as an auxiliary agent for activating the fly ash; the solid-liquid ratio of the secondary activated fly ash to the mixed acid is 1: 4;
(5) mixing the aluminum hydroxide prepared in the step (4) with 23% hydrochloric acid by mass, performing high-temperature and high-pressure acid dissolution, and then adjusting the basicity by using calcium aluminate mineral powder to obtain polyaluminium chloride; wherein, the conditions of high-temperature and high-pressure acid dissolution are that the temperature is 120 ℃, the pressure is 0.3MPa, and the reaction time is 3 h.
Example 2
A method for preparing flocculant polyaluminium chloride by using fly ash comprises the following steps:
(1) grinding and sieving the fly ash, then carrying out ultrasonic treatment on the fly ash for 10min at the temperature of 60 ℃ by using a sodium carbonate solution (the concentration of hydroxide ions is 1.5mol/L) and 400W, carrying out solid-liquid separation, washing to be neutral, and drying to obtain the alkali-treated fly ash;
(2) mixing the fly ash subjected to alkali treatment in the step (1), a composite sodium additive and water, performing 800W microwave activation for 5min, drying, crushing and sieving to obtain pre-activated fly ash; the composite sodium additive is a mixture of sodium carbonate, sodium chloride and sodium sulfate, and the mass ratio of the sodium carbonate to the sodium chloride to the sodium sulfate is 4: 0.5: 1; the mass ratio of the fly ash to the composite sodium assistant to the water is 1: 1: 2;
(3) calcining and activating the pre-activated fly ash prepared in the step (2) for 1.5h at 800 ℃, crushing and sieving to obtain secondary activated fly ash;
(4) acid leaching the secondary activated fly ash prepared in the step (3) in mixed acid with the pH value of 1 (the mass ratio of hydrochloric acid to sulfuric acid is 0.5: 1) at 90 ℃ for 2h, and carrying out solid-liquid separation to obtain an aluminum salt solution; regulatingThe pH value of the aluminum salt solution is 12.5, solid-liquid separation is carried out, and Fe is removed3+、Fe2+、Mg2+、Ca2+Plasma impurity ions; adjusting the pH value of the solution to 8, and carrying out solid-liquid separation to obtain aluminum hydroxide and filtrate; drying the filtrate to obtain a mixture of sodium sulfate and sodium chloride, which can be used as an auxiliary agent for activating the fly ash; the solid-liquid ratio of the secondary activated fly ash to the mixed acid is 1: 3;
(5) mixing the aluminum hydroxide prepared in the step (4) with hydrochloric acid with the mass fraction of 20%, performing high-temperature and high-pressure acid dissolution, and then adjusting the basicity by using calcium aluminate mineral powder to obtain polyaluminium chloride; wherein, the conditions of high-temperature and high-pressure acid dissolution are that the temperature is 110 ℃, the pressure is 0.4MPa, and the reaction time is 4 h.
Example 3
A method for preparing flocculant polyaluminium chloride by using fly ash comprises the following steps:
(1) grinding and sieving the fly ash, then carrying out ultrasonic treatment on the fly ash for 5min at 40 ℃ by using a sodium hydroxide solution (the concentration of hydroxide ions is 3mol/L) and 300W, carrying out solid-liquid separation, washing to be neutral, and drying to obtain the alkali-treated fly ash;
(2) mixing the fly ash subjected to alkali treatment in the step (1), a composite sodium additive and water, performing 600W microwave activation for 10min, drying, crushing and sieving to obtain pre-activated fly ash; the composite sodium additive is a mixture of sodium carbonate, sodium chloride and sodium sulfate, and the mass ratio of the sodium carbonate to the sodium chloride to the sodium sulfate is 4: 1.5: 1; the mass ratio of the fly ash to the composite sodium assistant to the water is 1: 1.5: 4;
(3) calcining and activating the pre-activated fly ash prepared in the step (2) for 1.2h at 850 ℃, crushing and sieving to obtain secondary activated fly ash;
(4) acid-leaching the secondary activated fly ash prepared in the step (3) in mixed acid with the pH value of 2.5 (the mass ratio of hydrochloric acid to sulfuric acid is 1.5: 1) at 110 ℃ for 1h, and carrying out solid-liquid separation to obtain an aluminum salt solution; adjusting the pH value of the aluminum salt solution to 12, carrying out solid-liquid separation, and removing Fe3+、Fe2+、Mg2+、Ca2+Plasma impurity ions; adjusting the pH value of the solution to 5, and carrying out solid-liquid separation to obtain aluminum hydroxide and filtrate; drying the filtrate to obtain a mixture of sodium sulfate and sodium chlorideUsed as an auxiliary agent for the activation of the fly ash; the solid-liquid ratio of the secondary activated fly ash to the mixed acid is 1: 6;
(5) mixing the aluminum hydroxide prepared in the step (4) with 25 mass percent hydrochloric acid, performing high-temperature and high-pressure acid dissolution, and then adjusting the basicity by using calcium aluminate mineral powder to obtain polyaluminium chloride; wherein, the conditions of high-temperature and high-pressure acid dissolution are that the temperature is 140 ℃, the pressure is 0.2MPa, and the reaction time is 2.5 h.
Comparative example 1
A method for preparing flocculant polyaluminium chloride by using fly ash comprises the following steps:
(1) grinding and sieving the fly ash, carrying out acid leaching for 1.5h in mixed acid with the pH value of 2 (the mass ratio of hydrochloric acid to sulfuric acid is 1: 1) at 106 ℃, and carrying out solid-liquid separation to obtain an aluminum salt solution; adjusting the pH value of the aluminum salt solution to 13, carrying out solid-liquid separation, and removing Fe3+、Fe2+、Mg2 +、Ca2+Plasma impurity ions; adjusting the pH value of the solution to 7, and carrying out solid-liquid separation to obtain aluminum hydroxide; the solid-liquid ratio of the fly ash to the mixed acid is 1: 4;
(2) mixing the aluminum hydroxide prepared in the step (1) with 23% hydrochloric acid by mass, performing high-temperature and high-pressure acid dissolution, and then adjusting the basicity by using calcium aluminate mineral powder to obtain polyaluminium chloride; wherein, the conditions of high-temperature and high-pressure acid dissolution are that the temperature is 120 ℃, the pressure is 0.3MPa, and the reaction time is 3 h.
Comparative example 2
A method for preparing flocculant polyaluminium chloride by using fly ash comprises the following steps:
(1) grinding and sieving the fly ash, mixing the ground fly ash with a sodium assistant sodium carbonate, calcining and activating for 1.3h at 820 ℃, crushing and sieving to obtain activated fly ash; wherein the mass ratio of the fly ash to the sodium assistant is 1: 1.2;
(2) acid-leaching the activated fly ash prepared in the step (1) in mixed acid with the pH value of 2 (the mass ratio of hydrochloric acid to sulfuric acid is 1: 1) at 106 ℃ for 1.5h, and carrying out solid-liquid separation to obtain an aluminum salt solution; adjusting the pH value of the aluminum salt solution to 13, carrying out solid-liquid separation, and removing Fe3+、Fe2+、Mg2+、Ca2+Plasma impurity ions; adjusting the pH value of the solution to 7, and performing solid-liquid separation to obtainTo aluminum hydroxide; the solid-liquid ratio of the activated fly ash to the mixed acid is 1: 4;
(3) mixing the aluminum hydroxide prepared in the step (2) with 23% hydrochloric acid by mass, performing high-temperature and high-pressure acid dissolution, and then adjusting the basicity by using calcium aluminate mineral powder to obtain polyaluminium chloride; wherein, the conditions of high-temperature and high-pressure acid dissolution are that the temperature is 120 ℃, the pressure is 0.3MPa, and the reaction time is 3 h.
Effects of the embodiment
(1)Al2O3Analysis of Leaching Rate
Titrating the content of aluminum ions in the solution by adopting an EDTA method, complexing EDTA and the aluminum ions when the pH value is 4.5-5.0, taking PAN as an indicator, and analyzing the content of the aluminum ions in the solution by using a method of back-dropping excessive EDTA solution by using a copper sulfate standard titration solution; according to the content of aluminum ions in the solution and Al in the fly ash raw material2O3The leaching rate is calculated according to the content of the active ingredients.
(2) Al is measured by adopting a method of the national standard 'water treatment agent-polyaluminium chloride' (GB15892-2003)2O3Content and basicity.
And (4) analyzing results:
the main chemical components of fly ash in examples 1 to 3 and comparative examples 1 to 2 are shown in table 1.
TABLE 1 main chemical composition of fly ash in examples 1 to 3
| Composition (I) | SiO2 | Al2O3 | Fe2O3 | CaO | TiO2 | K2O | MgO | Na2O | P2O5 |
| Content (wt%) | 49.31 | 40.4 | 1.88 | 2.89 | 1.53 | 0.43 | 0.31 | 0.17 | 0.15 |
The fly ash is not subjected to any treatment and is directly subjected to acid leaching, and the leaching rate of alumina is only 3.72% (comparative example 1, table 2), so that the target product cannot be obtained by adopting the direct acid leaching mode. Therefore, the activity of the fly ash is poor, and if an Al source is extracted by adopting an acid leaching method, the fly ash needs to be activated by an external means. In comparative example 2, the sodium assistant was used to add calcined activated fly ash, but the activation effect was not as good. After the coal ash is subjected to ultrasonic treatment by using the alkali solution, the microwave activation and the calcination activation are organically combined, and the compound sodium additive is added to ensure that SiO in the coal ash can be contained2、Al2O3The activity of the substances is obviously increased, the breakage of Si-Al bonds is promoted, and the Al is accelerated2O3Leaching rate of, aluminaThe leaching rate reaches more than 96 percent, wherein the composite sodium additive has obvious coordination and promotion effects, the reaction activity of the fly ash can be obviously improved, and the sodium sulfate and the sodium chloride can be recycled.
TABLE 2 analysis of results of alumina leaching rate after fly ash activation in examples 1-3
| Examples | Leaching rate (wt%) of alumina |
| Example 1 | 96.95 |
| Example 2 | 96.36 |
| Example 3 | 96.01 |
| Comparative example 1 | 3.72 |
| Comparative example 2 | 53.48 |
In addition, the poly aluminum chloride prepared in the examples 1 to 3 has higher Al through detection2O3Content and basicity (see table 3). Can be used for treating industrial wastewater, and has remarkable purification effect, and COD removal rate and chroma removal rate respectively reach above 82% and 80% (the adding amount of polyaluminium chloride is 400 mg/L).
TABLE 3 polyaluminum chlorides Al obtained in examples 1 to 32O3Analysis of content and basicity results
| Examples | Alumina content (wt%) | Degree of basicity (%) |
| Example 1 | 29.9 | 72 |
| Example 2 | 29.3 | 70 |
| Example 3 | 29.6 | 71 |
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (8)
1. A method for preparing flocculant polyaluminium chloride by using fly ash is characterized by comprising the following steps:
(1) grinding and sieving the fly ash, then carrying out ultrasonic treatment for 5-10 min at 40-60 ℃ by using an alkali solution, carrying out solid-liquid separation, washing to be neutral, and drying to obtain alkali-treated fly ash;
(2) mixing the coal ash subjected to alkali treatment in the step (1), a composite sodium additive and water, performing microwave activation at 600-800W for 5-10 min, drying, crushing and sieving to obtain pre-activated coal ash;
(3) calcining and activating the pre-activated fly ash prepared in the step (2) for 1-2 hours at 750-900 ℃, crushing and sieving to obtain secondary activated fly ash;
(4) performing acid leaching on the secondary activated fly ash prepared in the step (3), and performing solid-liquid separation to obtain an aluminum salt solution; adjusting the pH value of the aluminum salt solution to be not less than 12, and carrying out solid-liquid separation; adjusting the pH value of the solution to 5-8, and carrying out solid-liquid separation to obtain aluminum hydroxide and filtrate;
(5) dissolving the aluminum hydroxide prepared in the step (4) in acid at high temperature and high pressure, and then adjusting the basicity by using the calcium aluminate mineral powder to obtain polyaluminium chloride;
the alkaline solution in the step (1) is at least one of a sodium hydroxide solution and a sodium carbonate solution, wherein the concentration of hydroxide ions in the alkaline solution is 1.5-3 mol/L;
the compound sodium additive in the step (2) is a mixture of sodium carbonate, sodium chloride and sodium sulfate;
the mass ratio of the sodium carbonate to the sodium chloride to the sodium sulfate is 4 (0.5-1.5) to 1.
2. The method for preparing flocculant polyaluminum chloride from fly ash according to claim 1, wherein:
the power of the ultrasound in the step (1) is 300-400W.
3. The method for preparing flocculant polyaluminum chloride from fly ash according to claim 1, wherein:
the mass ratio of the fly ash, the composite sodium assistant and the water in the step (2) is 1: (1-1.5): (2-4).
4. The method for preparing flocculant polyaluminum chloride from fly ash according to claim 1, wherein:
the acid leaching reagent in the step (4) is mixed acid with the pH value of 1-2.5;
the mixed acid is a mixture of hydrochloric acid and sulfuric acid;
the mass ratio of the hydrochloric acid to the sulfuric acid is (0.5-1.5): 1.
5. the method for preparing flocculant polyaluminum chloride from fly ash according to claim 1, wherein:
the solid-to-liquid ratio of the secondary activated fly ash to the acid leaching reagent in the step (4) is 1: (3-6).
6. The method for preparing flocculant polyaluminum chloride from fly ash according to claim 1, wherein:
the acid leaching temperature in the step (4) is 90-110 ℃; the time of acid leaching is 1-2 h.
7. The method for preparing flocculant polyaluminum chloride from fly ash according to claim 1, wherein:
the acid solvent dissolved in the high-temperature and high-pressure acid in the step (5) is hydrochloric acid;
the mass fraction of the hydrochloric acid is 20-25%.
8. The method for preparing flocculant polyaluminum chloride from fly ash according to claim 1, wherein:
the high-temperature and high-pressure acid dissolution in the step (5) is carried out under the conditions of the temperature of 110-140 ℃, the pressure of 0.2-0.4 MPa and the reaction time of 2.5-4 h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710909253.4A CN107628632B (en) | 2017-09-29 | 2017-09-29 | Method for preparing flocculant polyaluminium chloride by using fly ash |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710909253.4A CN107628632B (en) | 2017-09-29 | 2017-09-29 | Method for preparing flocculant polyaluminium chloride by using fly ash |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107628632A CN107628632A (en) | 2018-01-26 |
| CN107628632B true CN107628632B (en) | 2020-04-17 |
Family
ID=61104615
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710909253.4A Active CN107628632B (en) | 2017-09-29 | 2017-09-29 | Method for preparing flocculant polyaluminium chloride by using fly ash |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107628632B (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108893612A (en) * | 2018-08-06 | 2018-11-27 | 昆明理工大学 | The recovery method of aluminium in a kind of flyash |
| CN109721092A (en) * | 2019-01-24 | 2019-05-07 | 鄂尔多斯市蓝天白云环保材料有限责任公司 | The preparation method and its gained aluminium polychloride and purposes of a kind of aluminium polychloride |
| CN109777960B (en) * | 2019-02-25 | 2020-12-01 | 河北工程大学 | A method for separating and recovering lithium and aluminum from fly ash |
| CN112662444B (en) * | 2019-10-16 | 2022-09-13 | 柳晶（溧阳）环保科技有限公司 | Method for casting coal powder in dedusting ash by ultrasonic separation |
| CN112028099A (en) * | 2020-08-20 | 2020-12-04 | 楚祯劼 | Clean production process for preparing polyaluminum chloride from fly ash |
| CN113003684B (en) * | 2021-03-02 | 2022-07-08 | 常熟理工学院 | A method and product for simultaneously preparing silicon nitride and aluminum-iron-calcium-based flocculants by using fly ash |
| CN115323173B (en) * | 2022-07-06 | 2024-05-17 | 福建有道贵金属材料科技有限公司 | A cyanide-free recovery method for precious metal-containing solid waste |
| CN116040669B (en) * | 2023-03-31 | 2023-08-04 | 内蒙古蒙泰集团有限公司 | Preparation method of polyaluminum chloride |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE531166C2 (en) * | 2007-06-08 | 2009-01-07 | Kemira Kemi Ab | Process for the preparation of polyaluminum salts |
| JP2009242226A (en) * | 2008-03-13 | 2009-10-22 | Denso Corp | Method for producing alumina particles |
| CN102107878B (en) * | 2010-11-10 | 2013-01-23 | 内蒙古科技大学 | Method for synthesizing fly ash zeolite by alkali fusion-microwave process |
| CN105621435A (en) * | 2015-12-25 | 2016-06-01 | 常州大学 | Method for treating high-concentration ammonia-nitrogen wastewater with molecular sieve prepared from flyash |
-
2017
- 2017-09-29 CN CN201710909253.4A patent/CN107628632B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN107628632A (en) | 2018-01-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107628632B (en) | Method for preparing flocculant polyaluminium chloride by using fly ash | |
| CN113968716A (en) | Harmless treatment method for electrolytic manganese slag | |
| CN105776150A (en) | Method for cooperative activation of fly ash and decomposition of gypsum for recovery of sulfur resource | |
| CN106892444A (en) | A kind of method of utilization waste hydrochloric acid and aluminium ash production polyaluminium chloride water purification agent | |
| CN113213498B (en) | Cement-based material carbonization recycling method and calcium carbonate whisker material | |
| CN104129934A (en) | Cementing material containing silicon-calcium slag and preparation method thereof | |
| CN112408821A (en) | Method for producing high-iron sulphoaluminate cement by utilizing red mud and aluminum ash | |
| CN107973327A (en) | A kind of impurity-removing method of red mud wash liquor and the production method of boehmite | |
| WO2013143335A1 (en) | Method for extracting aluminium oxide in fly ash by alkaline process | |
| CN106830722B (en) | Organic wastewater cooperates with the system and method for Industrial Solid Waste preparation ultrahigh water filler | |
| CN107473353B (en) | Preparation method of flocculant polyaluminum ferric chloride | |
| CN114804668A (en) | Preparation method of activated carbon-fixing material for producing recycled aggregate | |
| CN107445185A (en) | A kind of coal ash for manufacturing for aluminium polychloride method | |
| JP5831914B2 (en) | Water treatment method | |
| CN108558035A (en) | A kind of heavy metal-polluted water treatment agent and preparation method thereof | |
| CN115417409B (en) | Method for reinforcing red mud carbon fixation through cooperation of solid wastes in multi-production industry | |
| JP2011101830A (en) | Water treatment agent and water treatment method | |
| CN107445498A (en) | A kind of preparation method of phosphogypsum powder coal ash composite gelled material | |
| WO2023004927A1 (en) | Full-quantitative overall utilization method for step-by-step recovery of iron, sodium and tailings from bayer red mud | |
| CN112546529B (en) | Process for realizing dealkalization of high-alkalinity red mud by utilizing industrial waste residues and waste gases | |
| CN101058431A (en) | Method of extracting aluminum oxide | |
| CN101665278A (en) | Compound phosphorus removal flocculating agent for water treatment | |
| CN109280776B (en) | A kind of method for recovering chromium in electroplating sludge by sub-molten salt method | |
| CN114804794B (en) | Chloride ion curing agent for ammonia-soda process caustic sludge as well as preparation method and application of chloride ion curing agent | |
| CN113697834B (en) | Method for preparing friedel-crafts salt from titanium extraction slag and friedel-crafts salt |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20200319 Address after: 063021 South Road, modern equipment manufacturing industrial zone, Kaiping District, Tangshan City, Hebei Province Applicant after: Tangshan Zhongxu industrial water treatment Co., Ltd Address before: 511340 Xintang City, Guangzhou province Zengcheng District, the town of the village of big East Lane, Lane No. three, Lane 13, No. Applicant before: GUANGZHOU BAIXING NETWORK TECHNOLOGY Co.,Ltd. |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |