CN86106414B - Electrolytic method for treating wastewater containing vanadium and chromium - Google Patents

Electrolytic method for treating wastewater containing vanadium and chromium Download PDF

Info

Publication number
CN86106414B
CN86106414B CN86106414A CN86106414A CN86106414B CN 86106414 B CN86106414 B CN 86106414B CN 86106414 A CN86106414 A CN 86106414A CN 86106414 A CN86106414 A CN 86106414A CN 86106414 B CN86106414 B CN 86106414B
Authority
CN
China
Prior art keywords
vanadium
chromium
iron
electrolysis
water
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.)
Expired
Application number
CN86106414A
Other languages
Chinese (zh)
Other versions
CN86106414A (en
Inventor
程正东
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Central Iron and Steel Research Institute
Original Assignee
Central Iron and Steel Research Institute
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Central Iron and Steel Research Institute filed Critical Central Iron and Steel Research Institute
Priority to CN86106414A priority Critical patent/CN86106414B/en
Publication of CN86106414A publication Critical patent/CN86106414A/en
Publication of CN86106414B publication Critical patent/CN86106414B/en
Expired legal-status Critical Current

Links

Images

Landscapes

  • Treatment Of Water By Oxidation Or Reduction (AREA)
  • Water Treatment By Electricity Or Magnetism (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)
  • Electrolytic Production Of Metals (AREA)

Abstract

The present invention belongs to the treatment of industrial wastewater, which is mainly suitable for the treatment of vanadium and chromium containing wastewater. After being dissolved by acid and prereduced, the wastewater is electrolyzed; the electrochemical solution of an iron cathode generates ferrous ions which reduce hexavalent chrome into trivalent chromium; through cathode reaction, quinquevalence vanadium is reduced into quadrivalence vanadium; iron hydroxide absorbs the quinquevalence vanadium; finally, chromium, vanadium and iron are precipitated in the mode of hydroxide to obtain purified water of which Cr<6+> is less than 0.5 and V is less than 0.4 milligram per liter, and sediments with rich vanadium and chromium. Chemical additives are not need in the electrolytic treatment; vanadium removal depends on electrolysis side reaction without extra electrolysis consumption; sodium salt is not needed adding to the sediments; through calcination and water immersion, 80% of V2O5 is recovered.

Description

Electrolytic method for treating wastewater containing vanadium and chromium
The invention belongs to Industrial Wastewater Treatment.Be applicable to that mainly vanadium factory contains the processing of chromium vanadium-containing water.
Vanadium factory will discharge a large amount of waste water aborning, and it is acid that this class waste water is usually, contains Cr 2O 2- 7CrO 2- 4, VO + 2, H 3V 2O - 7Deng sexavalent chrome and pentavalent vanadium ion, contain a large amount of sodium salts and free acid in addition.Wherein to the harm of human body and animals and plants maximum be sexavalent chrome, pentavalent vanadium ion.
Vanadium factory and office manage this class waste water and continue to use ferrous sulfate reduction-lime neutralisation for a long time.There is the raw materials consumption height in this method, and sediment weight is big, and valuable metal such as can't reclaim at problem.The secondary pollution of sediment has become problem anxious to be solved.
Domestic several unit once adopted ion exchange method to handle vanadium factory waste water, and reclaimed vanadium and chromium respectively.After this method is handled, final discharge water Cr 6+＜0.5, V 5+＜1 mg/litre.Deutsches Reichs-Patent DE3136002(1983) stresses the recovery of vanadium in the waste water, chromium.Adopt iron filings or ferrous sulfate at first to remove vanadium, from settling, reclaim V then 2O 5Remove the vanadium tail washings and contain vanadium 10～30 mg/litre.Tail washings is through SO 2Behind the reduction of hexavalent chromium, produce chromic oxide by operations such as purification, dryings again.Aforesaid method all need add acid, alkali and other chemical agent, can reduce discharging water quality.Handle and reclaim complex process in addition, removing the vanadium degree of depth also is problem inadequately.
The electrolytic process processing waste water containing chrome has industrial application.Except that adding NaCl, suppress iron anode passivation and the reduction power consumption by need in the processing, cathodic reduction in the electrolysis, and side reactions such as ironic hydroxide absorption are also underused, and current consumption is also big.
The object of the present invention is to provide a kind of electrolysis process of handling vanadium factory acid vanadium-containing chromium-containing water.This method not only technology is simple, need not to add chemical agent; And the purification of waste water degree of depth is big, and sediment weight is little; The enrichment of vanadium chromium is beneficial to vanadium extraction in the sediment; Income that vanadium extraction obtains is portion or all offset the electrolysis treatment expense greatly, and promptly this method resulting cost is low.
The present invention handles vanadium factory acid vanadium-containing chromium-containing water with electrolytic process.Utilize the molten iron indirect reduction reaction of electrolytic process anode, sexavalent chrome, pentavalent vanadium ion are removed in cathodic reduction reaction and ironic hydroxide absorption reaction respectively, and waste water ph is raise, and obtain Cr 6+＜0.5, the water purification of V＜0.4 mg/litre and enrichment vanadium, the sediment of chromium.Water purification discharges with in a small amount of lime emulsified water and back, and sediment reclaims V with conventional extraction vanadium method 2O 5Tailings in vanadium extraction can be used as iron-smelting raw material or cement Additive.
Electrolysis vanadium factory waste water vanadium removal takes off the chromium principle
General steel plate as in the acidic vanadium chromium-containing wastewater of electrode immersion as electrolytic solution, is fed direct current and carries out electrolysis.There is reaction in the anode electrochemical dissolving:
Fe-2e＝Fe ++（1）
Fe ++There is following reaction in reducible hexavalent chromium:
Cr 2O 7＝+6Fe +++14H +＝2Cr 3++6Fe 3++7H 2O （2）
CrO 4＝+3Fe +++8H +＝Cr 3++3Fe 3++4H 2O （3）
Meanwhile, negative electrode generation evolving hydrogen reaction:
2H ++2e＝2〔H〕→H 2↑ （4）
((H) expression hydrogen in statu nascendi atom in the formula) raises the pH value of solution value gradually, generates Fe(OH) 3And Cr(OH) 3Hydrolytic precipitation.
Pentavalent vanadium ion can be in cathodic reduction, that is: during electrolysis
VO + 2+2H ++e＝VO +++H 2O （5）
H 3V 2O - 7+7H ++2e＝2VO +++5H 2O （6）
Also there are simultaneously (H) or H 2The reaction of reduction pentavalent vanadium ion:
VO + 2+1/2H 2＝VO +++OH -（7）
H 3V 2O - 7+H 2＝2VO +++5OH -（8）
VO ++After the pH value raises, with VO(OH) 2Or V 2O 42H 2The hydrolysis of O form settles out.
Flocculating colloid Fe(OH in addition) 3Can adsorb part pentavalent vanadium ion in the waste water, directly form and contain the vanadium codeposition body that flocculates based on ironic hydroxide.
The concrete technology that electrolytic process processing vanadium factory contains the vanadium chromate waste water is as follows:
The technological process of this method is seen Fig. 1.
Among the figure, 1 is iron filings acid bath, and 2 is electrolyzer, and 3 is filter, and 4 is neutralization tank;
Contain the vanadium chromate waste water and enter iron filings acid bath 1 from waste pipe, the molten generation ferrous ion of iron filings acid makes hexavalent chromium part prereduction in the waste water.Waste water flows out from sour bath, enters electrolyzer 2 by pipeline, and the iron anode electrochemical dissolution produces ferrous ion and makes that hexavalent chrome reduction becomes trivalent chromium in the waste water in the electrolysis, and cathodic reaction is reduced into the tetravalence vanadium with the pentavalent vanadium, ironic hydroxide absorption pentavalent vanadium.Last vanadium, chromium and iron are coprecipitated with the ironic hydroxide form, obtain Cr 6+＜0.5v, V＜0.4 mg/litre, the sediment of the water purification of pH5～7 and enrichment vanadium, chromium.No chemical additives in the electrolysis treatment remove vanadium and rely on the electrolysis side reaction, do not have extra electrolysis.The water purification of mentioned component and sediment enter filter 3 simultaneously after the electrolysis, make slag, water sepn.The filter residue of discharging from filter enters the vanadium extraction operation after the mummification.Filtrate enters neutralization tank 4 by pipeline, through the neutralization of lime emulsified water, discharges after improving the pH value and removing remaining ferrous ion.
Now that above-mentioned each operation division is as follows:
1. prereduction
Prereduction is carried out in sour bath 1.Waste iron filing, vanadium slag are coagulated iron or the adopting electrolysis residual pole plate drops in the sour bath.After containing the vanadium chromate waste water and entering in the sour bath, the natural acidity that relies on waste water is dissolved iron filings etc.The ferrous sulfate that the molten process of acid generates makes the part hexavalent chrome reduction become trivalent chromium.Waste water ph is 2～3,40～80 ℃ of temperature, and solid-to-liquid ratio (ratio of iron filings weight and wastewater volume) 〉=1 contains Cr from the effusive waste liquid of sour bath 6+Be about about 200 mg/litre.
With waste iron filing sexavalent chrome in the sewage is carried out prereduction and handle, power consumption and iron loss in the time of can reducing electrolysis treatment significantly, thus reduce the cost of whole technology.
2. electrolysis
Electrolysis is carried out in electrolyzer 2.Electrolytic negative electrode and anode all adopt iron plate, and its thickness is 2～5 millimeters, and polar plate spacing is 12～18 millimeters, and utmost point water is than (electrode plate surface amasss the ratio with wastewater volume) 0.12～1.54 * 10 -2Rice 2/ liter.Battery lead plate connects with parallel way.Bottom of electrolytic tank feeds pressurized air and stirs.
Electrolysis time can calculate by the hexavalent chromium actual concentrations in the waste water.Timing equation for single groove electrolysis treatment at intermittence is:
Electrolysis time (branch)=0.0537 * CV/BA (9)
C is the hexavalent chromium concentration (mg/litre) in the waste water in the formula; V is processed wastewater volume (liter); B is a coulomb molten iron amount (milligram iron/coulomb); A is strength of current (ampere).Owing to there is the acidic leach of iron anode, B value is generally all greater than theoretical value (0.2895 milligram of iron/coulomb), is 2～3 waste water for pH, and the B value can be taken as 0.30～0.35.
During electrolysis,, make pentavalent vanadium ion in cathodic reduction, with V by above-mentioned reaction formula (5), (6), (7), (8) 2O 42H 2O form precipitation.The part pentavalent vanadium ion is adsorbed by ironic hydroxide.Go out so that pentavalent form and ironic hydroxide are coprecipitated.
Trace vanadium (V in the water purification 2O 5), the analysis of hexavalent chromium adopts benzoylphenylhydroxyamine extraction colorimetry and hexichol together with the hydrazine colorimetry respectively.
3. filter
Slag, water mixture through electrolysis treatment enter filter 3 by pipeline.The employing plate-and-frame filter press filters.Behind the filter residue dehydration and drying, collect and stack, as the secondary raw material of vanadium extraction; Filtrate enters neutralization tank.
4. neutralization
In and in neutralization tank 4, carry out.By the effusive filtrate of plate-and-frame filter press, still contain the ferrous ion of a small amount of surplus, filtrate pH is 5～7.In neutralization tank, add a spot of lime emulsified water, make pH rise to 8, can remove remaining ferrous ion simultaneously.
The consumption of filtrate per ton of neutralizing is: 0.2～0.4 kilogram in lime, and 20～40 kilograms in water, the filtrate neutralization is the safeguards of purification of water quality.The consumption of its lime and water is less than ferrous sulfate reduction-lime neutralisation greatly.
5. vanadium extraction
One of characteristics of the present invention are easier to extract vanadium from sediment (filter residue).
From mix slag, reclaim V 2O 5Key be to realize to greatest extent that vanadium chromium separates, the hexavalent chromium that electrolysis treatment is removed is unlikely to return again the vanadium extraction system.Vanadium in the sediment of the present invention exists with free vanadium oxide form basically, and it is different from the tailings in the vanadium extraction process.Although V in the slag 2O 5Grade lower, but adopt conventional roasting-water logging art breading, still can obtain to soak rate greater than 80% commentaries on classics.
During electrolysis, vanadium, chromium and iron are coprecipitated with oxyhydroxide, can carry or adsorb the sodium salt in the waste water, make it enter sediment in addition.Therefore from sediment, reclaim V 2O 5, need not to add sodium salt.
Sediment does not add sodium salt, and roasting is 1～2 hour under 800～900 ℃ oxidizing atmosphere, again through 80 ℃ of water-soluble leachings 40～60 minutes, V 2O 5Change and soak rate greater than 80%, the vanadium chromium concn is than (V in the immersion liquid 2O 5/ Cr 6+)＞58.Immersion liquid can be sent the precipitation operation.
The present invention solves the vanadium factory acid vanadium-containing chromium-containing water processing and valuable metal reclaims problem.Water purification degree of depth height, treatment process is simple, need not to add chemical agent, and sediment weight is little, takes off the chromium electric quantity consumption and is lower than the conventional electrolysis method for removing chromium.Vanadium chromium enrichment and contain sodium salt in the sediment is adopted common process, vanadium extraction rate＞80%.Income that vanadium extraction obtains is portion or all offset processing costs greatly.
Contain the chromium vanadium-containing water through what the present invention handled, its degree of purification height purifies the water that is discharged the back and reaches following index:
Cr 6+＜0.5 mg/litre
V＜0.4 mg/litre
pH≈8
Embodiment one
Electrolytic process is handled and is contained chromium vanadium-containing water small-scale test.
Containing the chromium vanadium-containing water with the vanadium factory without sour bath prereduction is raw material, has carried out 3 tests.With the cold-rolled steel sheet is electrode.The wastewater flow rate of 3 tests is respectively 250,200,200 milliliters, and current density is respectively 2.6,3.3,3.3 peace/decimetres 2, utmost point water ratio is respectively 1.23,1.54,1.54 * 10 -2Rice 2/ liter, interelectrode distance is 12 millimeters.Electrolysis time 7,20,18 minutes respectively.
Waste water composition, chrome alum concentration ratio (contained Cr in the waste water that test is adopted 6+With V 2O 5Ratio), input electric weight, electrolysis and test-results (purify composition, pH value, sediment weight and V 2O 5Content) etc. list table 1 in.
Embodiment two
Electrolytic process is handled and is contained the expanding test of chromium vanadium-containing water.
With the hot-rolled steel sheet is electrode, and containing the chromium vanadium-containing water with the vanadium factory that handles without prereduction is raw material, has carried out 8 tests.The wastewater flow rate of handling for 8 times is 86 liters, and current density is 0.15 peace/decimetre 2, utmost point water ratio is 0.12 * 10 -2Rice 2/ liter, 18 millimeters of interelectrode distances are taken as 0.3278 milligram of iron/coulomb according to formula (9) B value, and electrolysis time was followed successively by 140,130,105,100,120,110,145,140 minutes.
Handled waste water composition, chrome alum concentration ratio (Cr 6+/ V 2O 5), input electric weight, electrolysis and water purification become to grade and list table 2 in.
Embodiment three
The molten iron filings prereduction test of acid.
Test is carried out in sour bath.Carried out twice altogether.By solid-to-liquid ratio is 1, iron filings are dropped into the processed chromium that contains contain in the vanadic acid wastewater, and 40 ℃ of treatment temps, and stirred respectively 2 and 2.5 hours, before the pre-treatment, contain Cr in the waste water 6+Be respectively 380.8 and 544 mg/litre, the pH value is 2; After iron filings prereduction, Cr in the waste water 6+Be 206.4 mg/litre, pH=2.5, Cr 6+Reduction ratio be respectively 45.8 and 62.06%.
Find out by above, after prereduction is handled, portion C r 6+Obtain reduction, thereby power consumption and iron loss can reduce electrolysis treatment greatly the time have reduced cost.

Claims (8)

1, a kind of electrolytic process that adopts is handled the acid water treatment method that contains vanadium, chromate waste water, adopt iron anode reaction reduction of hexavalent chromium and iron cathode reaction pentavalent vanadium, by iron anode electrochemical dissolution and cathode hydrogen evolution reaction, generation can be adsorbed the removable ironic hydroxide multipolymer of chromium, vanadium ion to purify liquid waste.
2, method according to claim 1 is characterized in that electrolytic negative electrode and anode are steel plate, and its thickness is 2～5 millimeters, and polar plate spacing is 12～18 millimeters.
3, method according to claim 2 is characterized in that the utmost point water ratio that is adopted is 0.12～1.54 * 10 -2Square metre/liter.
4, method according to claim 3 is characterized in that its electrolysis time calculates with following formula:
Electrolysis time (minute)=0.0537 * CV/BA
C is hexavalent chromium concentration (mg/litre) in the formula; V is the volume (liter) of processed waste water; B is a coulomb molten iron amount (milligram iron/coulomb); A is strength of current (ampere).
5, method according to claim 4 is characterized in that when the pH value is 2～3 the span of B value is 0.30～0.35.
6, method according to claim 5 is characterized in that before electrolysis treatment earlier through the sexavalent chrome in the ferrous ion acid solution reducing waste water.
CN86106414A 1986-11-07 1986-11-07 Electrolytic method for treating wastewater containing vanadium and chromium Expired CN86106414B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN86106414A CN86106414B (en) 1986-11-07 1986-11-07 Electrolytic method for treating wastewater containing vanadium and chromium

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN86106414A CN86106414B (en) 1986-11-07 1986-11-07 Electrolytic method for treating wastewater containing vanadium and chromium

Publications (2)

Publication Number Publication Date
CN86106414A CN86106414A (en) 1988-05-04
CN86106414B true CN86106414B (en) 1988-06-08

Family

ID=4803197

Family Applications (1)

Application Number Title Priority Date Filing Date
CN86106414A Expired CN86106414B (en) 1986-11-07 1986-11-07 Electrolytic method for treating wastewater containing vanadium and chromium

Country Status (1)

Country Link
CN (1) CN86106414B (en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104058523B (en) * 2013-10-31 2015-12-30 攀钢集团攀枝花钢铁研究院有限公司 A kind for the treatment of process of vanadium oxide manufacture waste water
CN104150651B (en) * 2014-08-15 2016-08-24 中国科学院生态环境研究中心 A kind of electronation assisted electrochemical method removes chromic method in water
EP3452624B1 (en) * 2016-05-06 2023-07-19 Metso Outotec Finland Oy Method for removing selenium (vi) from water
CN107620090A (en) * 2017-11-07 2018-01-23 攀钢集团攀枝花钢铁研究院有限公司 The recovery method of vanadium and manganese in vanadium wastewater
CN108795991A (en) * 2018-05-30 2018-11-13 中南大学 A kind of method that pyrite promotes dissimilatory iron reduction bacterium reduction chromium as electron shuttle carrier
CN109293041B (en) * 2018-09-25 2021-05-18 成都兴蓉环保科技股份有限公司 Combined treatment method of waste sodium dichromate and emulsion
CN109678227B (en) * 2019-01-29 2022-03-01 华中农业大学 Method for removing heavy metal anion pollution in water body by electrochemically reducing iron oxide
CN111560524B (en) * 2020-06-15 2021-06-22 中国科学院过程工程研究所 Method for inhibiting reduction of sodium chromate in circulating liquid in vanadium slag vanadium-chromium co-extraction process
CN112794514B (en) * 2020-12-28 2022-09-09 大连博融新材料有限公司 Low-current electrolytic treatment method and device for antimony ions in vanadium-containing wastewater

Also Published As

Publication number Publication date
CN86106414A (en) 1988-05-04

Similar Documents

Publication Publication Date Title
CN101811793B (en) Pretreatment process of chromium-containing wastewater
CN107857426B (en) Comprehensive treatment method for phosphorus-containing wastewater
CN102070261A (en) Hexavalent chromium-containing waste water treatment method
CN86106414B (en) Electrolytic method for treating wastewater containing vanadium and chromium
CN106277456A (en) A kind of waste electroplating liquor containing chromium resource prepares the method that ferrochrome is black
CN107244719A (en) A kind of method of the periodicity treatment of chromium containing wastewater of falling pole
CN113087040A (en) Novel defluorinating agent and fluorine-containing waste liquid treatment process
CN110255823B (en) High-zinc high-ammonia-nitrogen high-thiourea wastewater treatment process
CN101591056B (en) Flocculating agent for treating water and preparation and application thereof
CN101591057B (en) Flocculating agent with denitriding function for treating water and preparation and application thereof
CN113026043B (en) Electrolysis equipment and application thereof
US20240270613A1 (en) Treatment method of wastewater containing ferricyanide complex and oxalate
PL176064B1 (en) Method of regeneratively treating waste water from production of lead-acid accumulators
CN105417800A (en) Environment-friendly method for removing nitrate nitrogen in waste water
US3909372A (en) Process for treating spent iron-containing chromium plating solution to remove iron values contained therein and regenerate the solution
CN101891321A (en) Method for treating metallurgical off-gas acid-making waste water
CN113788520A (en) Iron-chromium-aluminum pickling process, wastewater treatment method and wastewater treatment device
CN208648942U (en) A kind of device based on persulfate processing desulfurization wastewater
CN103896423A (en) Processing method of stainless steel neutral salt electrolytic waste liquid
CN109879379A (en) A kind of three-stage electricity Fenton reduces the system and method for waste water COD
CN116477785B (en) Environment-friendly treatment method for wastewater generated in hot galvanizing production process
CN110240251A (en) Chemical nickle-plating wastewater removes nickel method
CN210974235U (en) Treatment device for treating wastewater containing mercury ions and hexavalent chromium ions
CN118221248B (en) Method for removing sulfate radical in acid mine wastewater
CN210103454U (en) Waste acid recovery device for treating steel pickling waste liquid

Legal Events

Date Code Title Description
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
PB01 Publication
C06 Publication
C13 Decision
GR02 Examined patent application
C14 Grant of patent or utility model
GR01 Patent grant
C19 Lapse of patent right due to non-payment of the annual fee
CF01 Termination of patent right due to non-payment of annual fee