Background technology
Polysilicate aluminum ferric chloride is a kind of composite type inorganic polymer flocculation agent growing up on silicic acid and aluminium salt, Ferric Salt Flocculants basis gathering.Electronegative poly-silicic acid has higher relative molecular mass, and the colloidal solid in water body is had to very strong adsorptive power; And polymeric aluminum molysite can be hydrolyzed the hydrolysis hydroxyl ion of the lotus that forms serial band positive electricity in water, there is stronger charge neutrality ability.The two is combined into a kind of product, becomes the inorganic polymer coagulant simultaneously with charge neutrality effect and adsorption bridging ability.Good owing to thering is coagulation effect, process low temperature, low-cloudy water has special efficacy, low price, the feature such as kish ion in water is low, causes the very big concern of field of water treatment.
Aluminium foil spent pickle liquor mainly refer to that electric aluminum foil factory etching process produces containing aluminic acid wastewater.An electronic Aluminum Foil Factory is produced this waste liquid daily more than 1000 tons, tens of families of national existing the type enterprise.At present, to the processing of this spent acid be with in alkali and after emit, so not only to consume a large amount of alkali, and can produce a large amount of aluminium hydroxide solid residues, bring new environmental problem.
Iron and steel pickling waste liquid is typical metal pickling waste liquid, all containing a large amount of acidic substance and ferrous ion, if directly discharge will cause severe contamination to receiving water body and edatope.Existing treatment process is to adopt that air distillation---condensation method reclaims hydrochloric acid, but the residual HCl of this method is too high, and higher to temperature requirement in production, energy consumption is large, and equipment corrosion is serious, and more serious to the damage ratio of environment.
Electric aluminum foil factory etching process produce containing aluminic acid wastewater, before being discharged into sewage network, need to pass through sewage disposal.In this treatment process, an important step is carried out acid-base neutralisation processing to these acid waste waters exactly, raising along with the pH value of waste water, there is hydrolysis and form aluminum hydroxide precipitation in the aluminium salt in waste water, in follow-up pulp water separating device, be retained down, after drying, become solid aluminum hydroxide material (being commonly called as aluminium slag).This unbodied aluminium hydroxide solid has higher activity, can under relatively mild condition, by acid, be dissolved.
For aluminium foil acid, steel acid lotion and the aluminium slag of utilizing of the present invention, for raw material, prepare the polysilicate aluminum ferric chloride polymeric flocculant with good shelf-stability and flocculating property, have not yet to see bibliographical information.
Summary of the invention
The object of this invention is to provide a kind of method of utilizing aluminium foil acid, ferrous acid to prepare aluminum chlorate of polymerized silicic acid iron, is to utilize the aluminium foil acid (AlCl producing after electronic aluminum foil corrosion
3content is at 7-15%, HCl content 2.0-4.0%), (Fe content is 5-10% to iron and steel ferrous acid washing lotion, H
2sO
4content 3-5%), water glass and aluminium slag production waste are processed the method with efficient flocculant polysilicate aluminum ferric chloride.The present invention is in order to utilize industrial produced wastes, to promote green production process, providing a kind of to the turbidity of sewage, the preparation method of chroma removal rate PASFC high, that stability in storage is good and the method for application and sewage disposal thereof.
In order to address the above problem, the technical solution used in the present invention is:
A method of preparing aluminum chlorate of polymerized silicic acid iron, comprise the steps: (1) by 100 parts of steel acid lotions with after the aluminium foil acid of 200 parts mixes, then react 0.5-2 hour with 1.5-3 part oxygenant chloric acid sodium, control temperature of reaction 50-80 ℃; (2) continue to add the aluminium foil acid of 800-1300 part, controlling mixing solutions temperature is 40-60 ℃, according to the Si/ of 0.05-0.2 (Al+Fe) ratio, drips metasilicate pentahydrate sodium solution 100-300 part, reaction 1-4 hour; (3) then add the Al (OH) of 65-120 part
3aluminium slag makes mixing solutions alkalization polymerization, ageing, controls pH value between 2.0-3.5, and reaction 1-3 hour, finally makes inorganic macromolecule flocculant poly silicic acid aluminium chloride ferrum product.
An aluminum chlorate of polymerized silicic acid ferrous solution that adopts aforesaid method to prepare, it is a kind of aluminum chlorate of polymerized silicic acid iron inorganic polymer copolymer solution.Its application method is:
With distilled water diluting: be 30-50% by polysilicate aluminum ferric chloride solution dilution to concentration, with hydrochloric acid by the pH regulator of waste water to 7.0-8.0, then respectively according to aluminum chlorate of polymerized silicic acid ferric flocculant: the ratio that the volume ratio of sewage is 0.5-5:1000 under agitation slowly adds in waste water, stir 2-5 minute, described sewage is printing and dyeing, life or industrial sewage.
The present invention utilizes the main component FeSO in iron and steel Acidic Liquid
4and H
2sO
4, aluminium foil acid main component AlCl
3and the main component Al (OH) of HCl, aluminium slag
3deng trade waste, be raw material, auxiliary metasilicate pentahydrate sodium, makes Fe by oxidation
2+ion conversion is Fe
3+the techniques such as ion, molten, the polymerization of acid, under comparatively gentle reaction conditions, utilize aluminium slag in pH value and the basicity of active aluminium hydroxide constituent adjustment mixing solutions, form stable multipolymer polysilicate aluminum ferric chloride inorganic polymer.Key of the present invention is to make full use of industrial waste raw material, using aluminium slag as consumption acid starting material, promotes aluminium, silicon, iron to form stable multipolymer, and the polymerization red-tape operati of product is strong, good stability, be convenient to suitability for industrialized production.Not only solve the emission problem of these wastes, and can bring considerable economic benefit for enterprise, product again can reuse and sewage treatment process, the green production of promoting enterprise with develop a circular economy.
The invention has the beneficial effects as follows: the aluminum chlorate of polymerized silicic acid iron that adopts the method to prepare can be widely used in the processing of dyeing waste water, sanitary sewage, trade effluent etc., have very by force except COD, decolouring, turbidity removal ability, and form that alumen ustum is large and closely knit, the alumen ustum settling time is short.
Embodiment
Embodiment 1
Utilize aluminium foil acid, ferrous acid to prepare a method for aluminum chlorate of polymerized silicic acid iron, comprise the steps:
(1) 100 parts of steel acid lotions, are reacted with 1.5 parts of oxygenant chloric acid sodium after sour mixing with the aluminium foil of 200 parts, control temperature 50 C, 0.5 hour reaction times;
(2) continue to add the aluminium foil acid of 800 parts, controlling mixing solutions temperature is 40 ℃, and the Si/ according to 0.05 (Al+Fe) ratio drips 100 parts of metasilicate pentahydrate sodium solution, reacts 1 hour;
(3) then add the Al (OH) of 70 parts
3aluminium slag makes mixing solutions alkalization polymerization, ageing, controls pH value 2.0, reacts 1 hour, finally makes inorganic macromolecule flocculant poly silicic acid aluminium chloride ferrum solution.
Embodiment 2
Utilize aluminium foil acid, ferrous acid to prepare a method for aluminum chlorate of polymerized silicic acid iron, comprise the steps:
(1) 100 parts of steel acid lotions, are reacted with 2.0 parts of oxygenant chloric acid sodium after sour mixing with the aluminium foil of 200 parts, control temperature 60 C, 1 hour reaction times;
(2) continue to add the aluminium foil acid of 1000 parts, controlling mixing solutions temperature is 50 ℃, and the Si/ according to 0.1 (Al+Fe) ratio drips 200 parts of metasilicate pentahydrate sodium solution, reacts 2 hours;
(3) then add the Al (OH) of 86 parts
3aluminium slag makes mixing solutions alkalization polymerization, ageing, controls pH value 2.5, reacts 2 hours, finally makes inorganic macromolecule flocculant poly silicic acid aluminium chloride ferrum solution.
Embodiment 3
Utilize aluminium foil acid, ferrous acid to prepare a method for aluminum chlorate of polymerized silicic acid iron, comprise the steps:
(1) 100 parts of steel acid lotions, are reacted with 3 parts of oxygenant chloric acid sodium after sour mixing with the aluminium foil of 200 parts, control 80 ℃ of temperature, 2 hours reaction times;
(2) continue to add the aluminium foil acid of 1300 parts, controlling mixing solutions temperature is 60 ℃, and the Si/ according to 0.2 (Al+Fe) ratio drips 300 parts of metasilicate pentahydrate sodium solution, reacts 4 hours;
(3) then add the Al (OH) of 112 parts
3aluminium slag makes mixing solutions alkalization polymerization, ageing, controls pH value 3.5, reacts 3 hours, finally makes inorganic macromolecule flocculant poly silicic acid aluminium chloride ferrum solution.
Embodiment 4
A kind of aluminum chlorate of polymerized silicic acid iron product the concrete embodiment of preparation method:
(1) oxidation
With the steel acid lotion of Zhaoqing Bi Jiang Environmental Protection Technology Co., Ltd, the aluminium foil of Zhaoqing Huafeng Electronic Aluminum Foil Co., Ltd. acid and commercially available technical grade NaClO
3for raw material, steel acid lotion (ferrous acid) main component: FeSO wherein
4, 23.5%; H
2sO
4, 6.5%; All the other are water; Aluminium foil acid main chemical compositions: AlCl
3, 10.2%; HCl, 3.6%; All the other are water; Sodium chlorate is technical grade, NaClO3%>=98%.
After the acid of 20-40g ferrous acid and 40-80g aluminium foil is mixed, add 0.62-1.28g sodium chlorate after being warmed up to 70 ℃, be incubated and stir 1-2 hour, by Fe
2+all be converted into Fe
3+;
(2) silicic acid activation
To step (1), make containing Fe
3+in aluminium foil acid, add the acid of 160-320g aluminium foil, controlling temperature is 40-60 ℃ and stirring, by 12-25g Na
2siO
35H
2o wiring solution-forming, slowly adds in mixing solutions, is incubated and stirs 1-3h, obtains the oligomeric composite solution of aluminium-iron-silicon.
(3) alkalization, polymerization, produce aluminum chlorate of polymerized silicic acid iron
The oligomer solution that step (2) is made is warmed up to 80 ℃, maintains to stir also slowly to add 14.5-30g aluminium slag (Al (OH)
3%>=82%), stirring reaction, copolymer-1-3h, obtain copolymerized macromolecule flocculant poly silicic acid aluminium chloride ferrum.
The polysilicate aluminum ferric chloride flocculant that the present invention is made is for dyeing waste water, and contrast with the treatment effect of polymerize aluminum chloride (PAC) and aluminium iron polychloride (PAFC), dyeing waste water used is taken from Zhaoqing, Guangdong Province dyeing and finishing factory, and sewage quality is as follows:
pH |
COD
Cr/(mg/L)
|
Colourity/degree |
Turbidity/NTU |
9.2 |
355.6 |
1018 |
35.2 |
Get a certain amount of aluminum chlorate of polymerized silicic acid ferrous solution, polymerize aluminum chloride and aluminium iron polychloride solid phase prod, with distilled water diluting by the 30-50% to concentration according to silicic acid aluminium chloride ferrum solution dilution, and the polymerize aluminum chloride of solid and aluminium iron polychloride are diluted to same concentrations, with hydrochloric acid by the pH regulator of waste water to 7.0-8.0, then respectively according to flocculation agent: the ratio that the volume ratio of dyeing waste water is 1000:0.5-5 under agitation slowly adds in waste water, stir after 2-5 minute after static certain hour, get supernatant liquid and analyze water quality, result is as follows:
Flocculation agent |
COD
CrClearance/%
|
Chroma removal rate/% |
Turbidity removal rate/% |
Alumen ustum settling time/min |
PASFC |
81.5 |
90.3 |
97.6 |
4-8 |
PAFC |
72.3 |
72.9 |
85.5 |
7-12 |
PAC |
68.6 |
65.6 |
74.9 |
12-18 |
Compare with PAC, PAFC, in PASFC owing to being compounded with the performances such as adsorptive power, charge neutrality ability of poly-silicic acid, poly-aluminium and several flocculation agents of Polyferric Sulfate, the larger hydrolysis complexing product of aggressiveness of generation, because of
After this is added in water, can bring into play charge neutrality effect and strong adsorption bridging effect simultaneously, thereby show better turbidity removal, decolour and fall COD usefulness.