CN105502516A - Method for preparing polyferric chloride from steel pickling wastewater - Google Patents
Method for preparing polyferric chloride from steel pickling wastewater Download PDFInfo
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- CN105502516A CN105502516A CN201610084067.7A CN201610084067A CN105502516A CN 105502516 A CN105502516 A CN 105502516A CN 201610084067 A CN201610084067 A CN 201610084067A CN 105502516 A CN105502516 A CN 105502516A
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G49/00—Compounds of iron
- C01G49/10—Halides
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Abstract
The invention discloses a method for preparing polyferric chloride from steel pickling wastewater. The method comprises the following steps: (1) adding a reducing agent into the steel pickling wastewater, stirring, and allowing standing; (2) performing secondary purification treatment; (3) adding hydrochloric acid, an aqueous solution of a stabilizing agent, and introducing air for oxidizing while stirring is carried out; (4) periodically measuring the molar content of ferrous ions in the solution in the process of introducing the air, when the ferrous ions in the solution accounts for 5 to 40 percent of the total molar content of iron, stopping introducing the air, and adding an oxidizing agent to continuing oxidize the remaining ferrous ions till the solution contains no ferrous iron, so as to obtain yellowish-brown transparent polyferric chloride liquid. According to the method, the problem of the pollution to the environment caused by the steel pickling wastewater is solved thoroughly; waste is changed into treasure; the investment is low; the cost is low; the efficiency is high; the process is easy to operate; the production is safe and environmentally friendly; the obtained product is the yellowish-brown transparent liquid in appearance, can exist over six month stably, is good in flocculation effect, and can be widely applied to sewage treatment.
Description
Technical field
The present invention relates to inorganic polymer functional materials preparation field, particularly relate to a kind of method being prepared poly-iron chloride by iron and steel pickling waste liquid.
Background technology
As everyone knows, pickling is requisite process for treating surface in pickling iron and steel process, the zone of oxidation of the method removing steel surface of this technology chemistry.Containing a large amount of ferrous salts and remnants acid in spent acid solution after pickling, if do not add process just directly discharge, iron and steel pickling waste liquid causes huge harm by environment.Have been reported in the literature the treatment technology of pickling iron and steel spent acid solution, but the operation condition of these treatment processs is harsh, complex process, cost is high, is difficult to realize industrialization.Therefore, finding a kind of effective means to recycle pickling iron and steel spent acid solution, to make it to be converted into useful product be the task that we one of facing is urgent.Poly-ferric chloride is a kind of new and effective inorganic polymer coagulation water purification agent, i.e. water conditioner is chemical agent required in process water, domestic water, wastewater treatment process.Water purification agent be mainly used to control incrustation scale and mud formation, reduce foam, reduce contact with water material corrosion, except the suspended solids in anhydrating and toxic substance, deodorization and discoloration, demineralized water etc.By using poly-ferric chloride, the specification of quality that water reaches certain can be made.Along with in world wide to the needs of the attention of global ecological environment, Sustainable development and the development of new and high technology, from secondary resource, obtaining raw material, to prepare poly-ferric chloride purifying agent be that of a recycling treatment pickling iron and steel spent acid solution well selects.
Summary of the invention
The object of the invention is the difficult problem solving the technology that current domestic steel industry process iron and steel pickling waste liquid faces, a kind of method being prepared poly-iron chloride by iron and steel pickling waste liquid is provided.
Technical scheme of the present invention is summarized as follows:
Prepared a method for poly-iron chloride by iron and steel pickling waste liquid, comprise the steps:
(1) pre-treatment of iron and steel pickling waste liquid: get iron and steel pickling waste liquid, add reductive agent reduction ferric iron, make reductive agent mass content be 0.2% ~ 1%, stir, place 2 ?10h;
(2) secondary-cleaned process: under agitation, regulates pH=4 ~ 8 of pretreated iron and steel pickling waste liquid with alkali, add auxiliary agent and make final concentration be 45 ~ 70mg/l, at 40 ~ 80 DEG C, reaction 0.5-3h, leaves standstill, filters, obtain the solution after secondary-cleaned process, survey Fe in solution
alwaysmass concentration;
(3) add hydrochloric acid in the solution obtained to step (2) and make HCl and Fe
alwaysmass ratio be 0.45-0.55, add the aqueous solution of stablizer, make stablizer and Fe
alwaysmol ratio=0.12-0.30,15-70 DEG C, 100-400rpm stir under, with flow for 0.05 ~ 0.2m
3/ h passes into atmospheric oxidation;
(4) in the molar content passing into timing mensuration solution ferrous ions in air event, when solution ferrous ions accounts for the 5%-40% of the total molar content of iron, stop passing into air, add oxygenant and continue oxidizes residual ferrous ion, until not containing ferrous ion in solution, obtain the poly-iron chloride liquid that tawny is transparent.
The described reductive agent mass content of step (1) is preferably 0.5% ~ 1%.
Described reductive agent is preferably iron filings or scrap iron skin.
Step (2) secondary-cleaned process is preferably: under agitation, regulate pH=5 ~ 7 of pretreated iron and steel pickling waste liquid with alkali, add auxiliary agent and make final concentration be 50 ~ 65mg/l, at 50 ~ 65 DEG C, stir 0.5 ?3h, filter, solution after secondary treatment, survey Fe in solution
alwaysmass concentration.
Alkali is preferably sodium hydroxide, ammoniacal liquor, sodium carbonate or sodium bicarbonate.
Auxiliary agent is preferably polyacrylamide.
Stablizer be preferably in acetic acid, citric acid, phosphoric acid, phosphoric acid salt, monohydric phosphate, dihydrogen phosphate and silicic acid one or both.
Oxygenant is preferably H
2o
2or NaClO
3.
By method of the present invention, recycling treatment is carried out to iron and steel pickling waste liquid, raw without any produce in whole preparation process, thoroughly solve spent pickle liquor to the pollution of environment; Achieve by the inventive method and turn waste into wealth; Method investment of the present invention is low, cost is low, efficiency is high, technological operation is simple, production safety environmental protection, products obtained therefrom is the transparent poly-iron chloride liquid of tawny, can stable existence more than six months, flocculating effect is good, be widely used in sewage disposal, for steel industry process spent pickle liquor provides a kind of well technical scheme.
Embodiment
Below in conjunction with specific embodiment, the present invention is further illustrated, and the following examples understand the present invention better to enable those skilled in the art to, but do not impose any restrictions the present invention.
Embodiment 1
Prepared a method for poly-iron chloride by iron and steel pickling waste liquid, comprise the steps:
(1) pre-treatment of iron and steel pickling waste liquid: get iron and steel pickling waste liquid, adds iron reduction ferric iron, makes iron filings mass content be 0.2%, stirs, and places 10h;
(2) secondary-cleaned process: under agitation, regulates the pH=7 of pretreated iron and steel pickling waste liquid with ammoniacal liquor, add polyacrylamide and make final concentration be 50mg/l, at 65 DEG C, reaction 0.5h, leaves standstill, filters, obtain the solution after secondary-cleaned process, survey Fe in solution
alwaysmass concentration;
(3) add 17ml concentrated hydrochloric acid in the solution (mass concentration is 151.2g/L) obtained to 100ml step (2) and make HCl and Fe
alwaysmass ratio be 0.55, add the aqueous solution (stablizer is 5.65g sodium phosphate) of stablizer, make stablizer and Fe
alwaysmol ratio=0.12, at 70 DEG C, 400rpm stir under, take flow as 0.05m
3/ h passes into atmospheric oxidation;
(4) in the molar content passing into timing mensuration solution ferrous ions in air event, when solution ferrous ions accounts for 5% of the total molar content of iron, stop passing into air, add 5.7gNaClO
3continue oxidizes residual ferrous ion, until not containing ferrous ion in solution, obtain the poly-iron chloride liquid that 122.65ml tawny is transparent.Product can stable existence 8 months.
Embodiment 2
Prepared a method for poly-iron chloride by iron and steel pickling waste liquid, comprise the steps:
(1) pre-treatment of iron and steel pickling waste liquid: get iron and steel pickling waste liquid, adds scrap iron skin reduction ferric iron, makes scrap iron skin mass content be 0.5%, stir, place 5h;
(2) secondary-cleaned process: under agitation, regulates the pH=5 of pretreated iron and steel pickling waste liquid with aqueous sodium hydroxide solution, add polyacrylamide and make final concentration be 65mg/l, at 50 DEG C, reaction 1h, leaves standstill, filters, obtain the solution after secondary-cleaned process, survey Fe in solution
alwaysmass concentration;
(3) add 18ml concentrated hydrochloric acid in the solution (mass concentration is 135.52g/L) obtained to 100ml step (2) and make HCl and Fe
alwaysmass ratio be 0.55, add the aqueous solution of stablizer, (stablizer is 2.14g silicic acid and 1.2g acetic acid) makes stablizer and Fe
alwaysmol ratio=0.2, at 60 DEG C, 100rpm stir under, take flow as 0.1m
3/ h passes into atmospheric oxidation;
(4) in the molar content passing into timing mensuration solution ferrous ions in air event, when solution ferrous ions accounts for 40% of the total molar content of iron, stop passing into air, add 8.5gNaClO
3continue oxidizes residual ferrous ion, until not containing ferrous ion in solution, obtain the poly-iron chloride liquid that 125ml tawny is transparent.Product can stable existence 10 months.
Embodiment 3
Prepared a method for poly-iron chloride by iron and steel pickling waste liquid, comprise the steps:
(1) pre-treatment of iron and steel pickling waste liquid: get iron and steel pickling waste liquid, adds scrap iron skin reduction ferric iron, makes scrap iron skin mass content be 1%, stir, place 2h;
(2) secondary-cleaned process: under agitation, regulates the pH=4 of pretreated iron and steel pickling waste liquid with aqueous sodium carbonate, add polyacrylamide and make final concentration be 45mg/l, at 40 DEG C, reaction 3h, leaves standstill, filters, obtain the solution after secondary-cleaned process, survey Fe in solution
alwaysmass concentration;
(3) add 14ml concentrated hydrochloric acid in the solution (mass concentration is 161.84g/L) obtained to 100ml step (2) and make HCl and Fe
alwaysmass ratio be 0.45, add the aqueous solution (stablizer is 7.5g citric acid) of stablizer, make stablizer and Fe
alwaysmol ratio=0.30, at 15 DEG C, 300rpm stir under, take flow as 0.08m
3/ h passes into atmospheric oxidation;
Substitute citric acid with phosphoric acid or disodium-hydrogen, other same the present embodiment, prepare the poly-iron chloride liquid that corresponding tawny is transparent.
(4) in the molar content passing into timing mensuration solution ferrous ions in air event, when solution ferrous ions accounts for 30% of the total molar content of iron, stop passing into air, add 14gH
2o
2continue oxidizes residual ferrous ion, until not containing ferrous ion in solution, obtain the poly-iron chloride liquid that 132.5ml tawny is transparent.Product can stable existence 6 months.
Embodiment 4
Prepared a method for poly-iron chloride by iron and steel pickling waste liquid, comprise the steps:
(1) pre-treatment of iron and steel pickling waste liquid: get iron and steel pickling waste liquid, adds iron reduction ferric iron, makes iron filings mass content be 0.6%, stirs, and places 6h;
(2) secondary-cleaned process: under agitation, regulates the pH=8 of pretreated iron and steel pickling waste liquid with sodium bicarbonate aqueous solution, add polyacrylamide and make final concentration be 70mg/l, at 80 DEG C, reaction 1h, leaves standstill, filters, obtain the solution after secondary-cleaned process, survey Fe in solution
alwaysmass concentration;
(3) add 18ml concentrated hydrochloric acid in the solution (mass concentration is 161.84g/L) obtained to 100ml step (2) and make HCl and Fe
alwaysmass ratio be 0.52, add the aqueous solution (stablizer is 3.15g SODIUM PHOSPHATE, MONOBASIC and 2.2g acetic acid) of stablizer, make stablizer and Fe
alwaysmol ratio=0.15, at 60 DEG C, 400rpm stir under, take flow as 0.2m
3/ h passes into atmospheric oxidation;
(4) in the molar content passing into timing mensuration solution ferrous ions in air event, when solution ferrous ions accounts for 25% of the total molar content of iron, stop passing into air, add 12.5gH
2o
2continue oxidizes residual ferrous ion, until not containing ferrous ion in solution, obtain the poly-iron chloride liquid that 135.85ml tawny is transparent.Product can stable existence 8 months.
Claims (8)
1. prepared a method for poly-iron chloride by iron and steel pickling waste liquid, it is characterized in that comprising the steps:
(1) pre-treatment of iron and steel pickling waste liquid: get iron and steel pickling waste liquid, add reductive agent reduction ferric iron, make reductive agent mass content be 0.2% ~ 1%, stir, place 2 ?10h;
(2) secondary-cleaned process: under agitation, regulates pH=4 ~ 8 of pretreated iron and steel pickling waste liquid with alkali, add auxiliary agent and make final concentration be 45 ~ 70mg/l, at 40 ~ 80 DEG C, reaction 0.5-3h, leaves standstill, filters, obtain the solution after secondary-cleaned process, survey Fe in solution
alwaysmass concentration;
(3) add hydrochloric acid in the solution obtained to step (2) and make HCl and Fe
alwaysmass ratio be 0.45-0.55, add the aqueous solution of stablizer, make stablizer and Fe
alwaysmol ratio=0.12-0.30,15-70 DEG C, 100-400rpm stir under, with flow for 0.05 ~ 0.2m
3/ h passes into atmospheric oxidation;
(4) in the molar content passing into timing mensuration solution ferrous ions in air event, when solution ferrous ions accounts for the 5%-40% of the total molar content of iron, stop passing into air, add oxygenant and continue oxidizes residual ferrous ion, until not containing ferrous ion in solution, obtain the poly-iron chloride liquid that tawny is transparent.
2. method according to claim 1, is characterized in that the described reductive agent mass content of step (1) is 0.5% ~ 1%.
3. method according to claim 1 and 2, is characterized in that described reductive agent is iron filings or scrap iron skin.
4. method according to claim 1, it is characterized in that step (2) secondary-cleaned is treated to: under agitation, pH=5 ~ 7 of pretreated iron and steel pickling waste liquid are regulated with alkali, adding auxiliary agent makes final concentration be 50 ~ 65mg/l, at 50 ~ 65 DEG C, stir 0.5 ?3h, filter, solution after secondary treatment, survey Fe in solution
alwaysmass concentration.
5. the method according to claim 1 or 4, is characterized in that described alkali is sodium hydroxide, ammoniacal liquor, sodium carbonate or sodium bicarbonate.
6. the method according to claim 1 or 4, is characterized in that described auxiliary agent is polyacrylamide.
7. method according to claim 1, is characterized in that described stablizer is one or both in acetic acid, citric acid, phosphoric acid, phosphoric acid salt, monohydric phosphate, dihydrogen phosphate and silicic acid.
8. method according to claim 1, is characterized in that described oxygenant is H
2o
2or NaClO
3.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106379976A (en) * | 2016-08-30 | 2017-02-08 | 无锡市新都环保科技有限公司 | Equipment and method for preparing water treatment agent through using acidic iron-containing wastewater |
| CN107555486A (en) * | 2017-09-18 | 2018-01-09 | 唐山市斯瑞尔化工有限公司 | The preparation method and poly-iron chloride solid of poly-iron chloride solid |
| CN108033490A (en) * | 2017-12-12 | 2018-05-15 | 青岛市昌斯达环保科技有限公司 | A kind of production method and technique of high-performance poly-ferric chloride |
| CN109250762A (en) * | 2017-07-13 | 2019-01-22 | 鞍钢股份有限公司 | A method of poly-ferric chloride is prepared with steel hydrochloric acid pickling waste water |
| CN110316766A (en) * | 2019-07-17 | 2019-10-11 | 中信环境技术（广州）有限公司 | A kind of method of two-stage oxidizing waste hydrochloric acid containing iron preparation chlorination iron product |
| CN110615485A (en) * | 2019-09-05 | 2019-12-27 | 中信环境技术（广州）有限公司 | Continuous production method and application of polyferric chloride |
| CN111153477A (en) * | 2020-01-07 | 2020-05-15 | 斯瑞尔环境科技股份有限公司 | Preparation method of powdery polyferric chloride solid |
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| CN105271435A (en) * | 2015-10-06 | 2016-01-27 | 聊城大学 | Production technology for preparing polyferric chloride coagulant from seamless steel pipe acid-washing waste liquid |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106379976A (en) * | 2016-08-30 | 2017-02-08 | 无锡市新都环保科技有限公司 | Equipment and method for preparing water treatment agent through using acidic iron-containing wastewater |
| CN109250762A (en) * | 2017-07-13 | 2019-01-22 | 鞍钢股份有限公司 | A method of poly-ferric chloride is prepared with steel hydrochloric acid pickling waste water |
| CN107555486A (en) * | 2017-09-18 | 2018-01-09 | 唐山市斯瑞尔化工有限公司 | The preparation method and poly-iron chloride solid of poly-iron chloride solid |
| CN107555486B (en) * | 2017-09-18 | 2021-07-27 | 唐山市斯瑞尔化工有限公司 | Preparation method of polyferric chloride solid and polyferric chloride solid |
| CN108033490A (en) * | 2017-12-12 | 2018-05-15 | 青岛市昌斯达环保科技有限公司 | A kind of production method and technique of high-performance poly-ferric chloride |
| CN110316766A (en) * | 2019-07-17 | 2019-10-11 | 中信环境技术（广州）有限公司 | A kind of method of two-stage oxidizing waste hydrochloric acid containing iron preparation chlorination iron product |
| CN110615485A (en) * | 2019-09-05 | 2019-12-27 | 中信环境技术（广州）有限公司 | Continuous production method and application of polyferric chloride |
| CN110615485B (en) * | 2019-09-05 | 2022-03-25 | 中信环境技术（广州）有限公司 | Continuous production method and application of polyferric chloride |
| CN111153477A (en) * | 2020-01-07 | 2020-05-15 | 斯瑞尔环境科技股份有限公司 | Preparation method of powdery polyferric chloride solid |
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