CN108914136A - A kind of zinc-plated pre-treating technology of steel pipe - Google Patents
A kind of zinc-plated pre-treating technology of steel pipe Download PDFInfo
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- CN108914136A CN108914136A CN201810862511.2A CN201810862511A CN108914136A CN 108914136 A CN108914136 A CN 108914136A CN 201810862511 A CN201810862511 A CN 201810862511A CN 108914136 A CN108914136 A CN 108914136A
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- Prior art keywords
- pond
- acid
- solvent
- steel pipe
- acid pond
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Classifications
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/08—Iron or steel
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
- C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/36—Regeneration of waste pickling liquors
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G3/00—Apparatus for cleaning or pickling metallic material
- C23G3/04—Apparatus for cleaning or pickling metallic material for cleaning pipes
Abstract
The present invention provides a kind of zinc-plated pre-treating technologies of steel pipe, from front to back include sour treatment process, two-stage cleaning process and solvent treatment process, and sour treatment process includes eo-acid pond, old sour pond and spent acid pond；Solvent treatment process includes solvent cell and online iron removal step, and online iron removal step is by the ferrous ions and precipitating in solvent cell；Steel pipe first passes through old sour pond, removing rust and oxide skin are removed in eo-acid pond, washes away the excessive acid and ferrous ion of steel tube surface subsequently into two-stage dilute hydrochloric acid service sink, finally so that steel tube surface is formed fluxing agent film by solvent cell, subsequently into zinc-plated process.The present invention can reduce the dosage of acid, completely remove trade effluent and industrial sludge, while being also able to achieve the post-processing of the online deferrization functional and solvent mud of solvent, realize environmentally protective recycle.
Description
Technical field
The invention belongs to steel pipe processing technology fields, more particularly, to a kind of zinc-plated pre-treating technology of steel pipe.
Background technique
For steel pipe by rolling, rolling, welding, one layer of iron oxide is adhered on surface, must be gone before zinc-plated to steel pipe
It removes, otherwise will affect the zinc-plated of steel pipe.
Currently, the method for traditional removal oxidation iron is then carried out using clear water clear by hydrochloride derusting
It washes, it is therefore desirable to use a large amount of water, and the sewage for cleaning steel pipe is handled, be currently by being aerated sewage
In ferrous ion carry out oxidation precipitation, precipitating when need using highly basic sodium hydroxide, sewage after treatment returns
It returns and continues to clean steel pipe.A large amount of industrial sludge is generated in processing sewage ferrous ions precipitation process, can be generated
Environmental pollution.
Steel pipe after water cleaning, will carry out flux bath submergence technique, one layer of uniform solvent membrane be formed in steel tube surface, when molten
When agent is unsatisfactory for requirement in use, it can not be used continuously, solvent is needed to be passed into precipitation tank, then be added double
Oxygen water and ammonium hydroxide mixing, then pass through pump and are delivered in filter press and be separated by solid-liquid separation, and obtain regenerated solvent filtrate and return to
It is continued to use in flux bath.
Whole process water consumption is big, uses highly basic, dangerous；Large amount of sewage and sludge are generated, processing cost is increased；
Solvent is unable to on-line continuous use, needs interval that can just continue to use waste energy after treatment.
Summary of the invention
In view of this, the present invention is directed to propose a kind of zinc-plated pre-treating technology of steel pipe, can reduce the dosage of acid and water, no
Cleaning agent is being made using water, therefore without sewage disposal process, and is not generating industrial sludge.And realize solvent
Line continuous use.
In order to achieve the above objectives, the technical proposal of the invention is realized in this way：
A kind of zinc-plated pre-treating technology of steel pipe includes sour treatment process, two-stage dilute hydrochloric acid cleaning process and molten from front to back
Agent treatment process,
Sour treatment process includes that eo-acid pond, old sour pond and spent acid pond, eo-acid pond have the injection of concentrated hydrochloric acid；
Two-stage dilute hydrochloric acid cleaning process includes two-stage dilute hydrochloric acid pond；
Solvent treatment process includes solvent cell and online iron removal step, and online iron removal step is by the ferrous ion in solvent cell
It aoxidizes, precipitate and prepare ferroso-ferric oxide；
The process of steel pipe is：
Steel pipe first passes through old sour pond, removing rust and oxide skin are removed in eo-acid pond, subsequently into two-stage diluted acid pond by steel tube surface
Excessive acid and ferrous ion wash away, and finally so that steel tube surface is adhered to one layer of uniform solvent membrane by solvent cell, subsequently into
In zinc-plated process；
Acid process be：
Concentrated hydrochloric acid is added to eo-acid pond, after the solution use in eo-acid pond again into the solution in old sour pond, old sour pond
Enter spent acid pond after utilization, the reuse dilute hydrochloric acid that spent acid pond is obtained by low temperature distillation technology enters diluted acid pond, and to carry out two-stage clear
It washes, enters eo-acid pond after the solution use in diluted acid pond and concentrated hydrochloric acid configures eo-acid in proportion.
Further, the HCl concentration in eo-acid pond is maintained at 12%-18%, when the sour Baume degrees when eo-acid pond reaches 30, sentences
Surely become old sour pond, the sour Baume degrees in old acid pond is greater than 40, and while detecting the acidity in acid less than 1 is determined as spent acid pond, spent acid
The acid in pond steams dilute hydrochloric acid by 110 degrees Celsius of low temperature distillations, and the reuse dilute hydrochloric acid steamed returns in diluted acid pond, after distillation
Liquid of the residue comprising frerrous chloride obtains frerrous chloride solid after crystallization.
Further, diluted acid pond includes diluted acid pond I and diluted acid pond II, and steel pipe initially enters dilute after coming out from eo-acid pond
Sour pond I, subsequently into diluted acid pond II, the reuse dilute hydrochloric acid that spent acid pond distills out enters diluted acid pond II.
Further, online iron removal step be solvent from solvent cell through piping be passed through during sedimentation basin with dioxygen
Water and ammonium hydroxide carry out on-line mixing, control pH value between 4.8-5.0, form ferric hydroxide precipitate, then pass to solvent cell into
Andante formula filters pressing, filtered fluid, which returns to, forms circulation in solvent cell, also obtains filter cake i.e. solvent mud.
It further, include the NH of 170~210g/L in solvent cell4The ZnCl of Cl, 210~250g/L2。
Further, the addition molar ratio of hydrogen peroxide and ammonium hydroxide is 1：4.
Further, solvent is no less than 3 minutes with the time that hydrogen peroxide and ammonium hydroxide mix in the duct, guarantees ferrous ion
It all is oxidized to iron ion, pH value is adjusted by ammonium hydroxide, so that it is generated ferric hydroxide precipitate and is separated into filtrate solvent reuse,
Filter cake is solvent mud.
Further, solvent mud is dissolved by spent acid, is converted into ferroso-ferric oxide (iron oxide black) after adding alkali to heat up.
In entire technical process, the trend of steel pipe and the trend of acid are opposite.
Steel pipe is by the tandem in sour pond：Old acid pond, eo-acid pond, diluted acid pond I, diluted acid pond II, eo-acid pond, old acid
Pond, spent acid pond with technique operation, wherein acid sour Baume degrees change therewith, when the sour Baume degrees in eo-acid pond reaches 30
When, eo-acid pond becomes old sour pond, when the sour Baume degrees in old sour pond is greater than 40, becomes spent acid pond, spent acid pond is steamed by distillation
Reuse dilute hydrochloric acid out enters diluted acid pond II, and the dilute hydrochloric acid in the II of diluted acid pond flows to diluted acid pond I, forms the circulation of acid.
For steel pipe when by solvent cell, the acid and ferrous ion of steel tube surface enter solvent cell therewith.Solvent
Solvent, ferrous ion and acid in pond enter surge tank by pipeline and are precipitated, subsequently into plate type pressure filter, in pipeline
In with hydrogen peroxide and ammonium hydroxide carry out on-line mixing, hydrogen peroxide carries out ferrous ion to be oxidized to iron ion, and then iron ion is in ammonia
Precipitating is formed under the action of water, the filtrate cycle after plate type pressure filter filtering, which is returned in solvent cell, to be utilized.
Compared with the existing technology, the zinc-plated pre-treating technology of steel pipe of the present invention has the advantage that：
The zinc-plated pre-treating technology of steel pipe of the present invention has been saved by being circularly set for acid and has used water, eliminated waste water
Discharge, eliminate the generation of industrial sludge.The online iron removal step of solvent recycles solvent cell, improves and removes
Iron speed and working efficiency, reduce energy loss.
Detailed description of the invention
The attached drawing for constituting a part of the invention is used to provide further understanding of the present invention, schematic reality of the invention
It applies example and its explanation is used to explain the present invention, do not constitute improper limitations of the present invention.In the accompanying drawings：
Fig. 1 is the flow diagram of the zinc-plated pre-treating technology of steel pipe described in the embodiment of the present invention.
Specific embodiment
It should be noted that in the absence of conflict, the feature in embodiment and embodiment in the present invention can phase
Mutually combination.
The present invention will be described in detail below with reference to the accompanying drawings and embodiments.
For producing 300 tons of coating steel pipe daily.
Steel pipe initially enters the oxide skin and impurity that old sour pond impregnate removal surface, subsequently into eo-acid pond carry out into
The scale removal of one step, the oxide skin of steel pipe is reacted with the acid in old sour pond and eo-acid pond generates ferrous ion, but by
It is introduced into old sour pond in steel pipe, therefore the sour Baume degrees in old sour pond reaches high value prior to eo-acid pond, is passed through into eo-acid pond
Concentrated hydrochloric acid, so that the HCl concentration in eo-acid pond is maintained in 12%-18%, after steel pipe has obtained thorough processing in eo-acid pond,
Surface has the acid and ferrous ion of higher concentration, then passes through diluted acid pond I and diluted acid pond II for the high concentrated acid of steel tube surface
It is cleaned with ferrous ion, to be attached with a small amount of acid and a small amount of frerrous chloride on the steel pipe after process diluted acid pond II, so
Steel pipe enters solvent cell afterwards, there is the NH of 190g/L in solvent cell4The ZnCl of Cl and 220g/L2, steel pipe enter solvent cell after,
The acid and frerrous chloride of steel tube surface attachment will be dissolved into solvent cell, solvent slop, and the solvent polluted in solvent cell enters
Pipeline, carries out on-line mixing with hydrogen peroxide and ammonium hydroxide in the duct, and dioxygen water consumption 0.08t, ammonium hydroxide consume 0.16t, adds simultaneously
Solvent mud rinse filtrate 0.15t, is reacted jointly by hydrogen peroxide and ammonium hydroxide, and ferrous ions at ferric ion and are made it
Hydrolysis obtains ferric hydroxide precipitate, and acid reacts with ammonia water generation ammonium chloride.
By plate type pressure filter, filter cake i.e. solvent mud is obtained：Ferric hydroxide precipitate 0.2t, filtered fluid return in solvent cell.
Solvent mud is in iron black workshop, and by three-level rinsing, filters pressing, solvent mud rinse filtrate returns to production line flux bath, obtained filter cake
It is dissolved by spent acid, iron black (ferroso-ferric oxide) is converted into after adding alkali to heat up, accomplishes sludge zero discharge.
Eo-acid pond, old sour pond, spent acid pond, the operation with technique, wherein the sour Baume degrees of acid changes therewith, when eo-acid pond
In sour Baume degrees when reaching 30, eo-acid pond becomes old sour pond, when the sour Baume degrees in old sour pond reaches 40, becomes spent acid
Low temperature distillation is passed through in pond, spent acid pond, and the reuse dilute hydrochloric acid steamed enters diluted acid pond II, keeps the Baume degrees of diluted acid pond II less than 8,
Dilute hydrochloric acid in the II of diluted acid pond flows to diluted acid pond I using liquid level static pressure by the pipeline connected, keeps the Baume degrees of diluted acid pond I small
Dilute hydrochloric acid in 15, diluted acid pond I flows to eo-acid pond the pipeline of connection in the way of liquid level static pressure, in eo-acid pond
Concentrated hydrochloric acid mixing, keeps the HCl concentration in eo-acid pond to be maintained in 12%-18%, forms the circulation of acid.In production process in addition to
It is added into system outside new concentrated hydrochloric acid, not the participation of secondary water.Not external sewage effluent simultaneously, has accomplished the zero-emission of water
It uses.The solvent mud of output recycles rinse filtrate by rinsing, filters pressing, and spent acid dissolution is added in filter cake, adds alkali heating four oxygen of preparation
Change three-iron (iron oxide black), " turning waste into wealth " does not discharge sludge externally.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all in essence of the invention
Within mind and principle, any modification, equivalent replacement, improvement and so on be should all be included in the protection scope of the present invention.
Claims (8)
1. a kind of zinc-plated pre-treating technology of steel pipe, it is characterised in that：It from front to back include sour treatment process, the cleaning of two-stage dilute hydrochloric acid
Process and solvent treatment process,
Sour treatment process includes that eo-acid pond, old sour pond and spent acid pond, eo-acid pond have the injection of concentrated hydrochloric acid；
Two-stage dilute hydrochloric acid cleaning process includes two-stage diluted acid pond；
Solvent treatment process includes solvent cell and online iron removal step, and online iron removal step is by the ferrous ion oxygen in solvent cell
Change, precipitate and prepares ferroso-ferric oxide；
The process of steel pipe is：
Steel pipe first passes through old sour pond, removing rust and oxide skin are removed in eo-acid pond, will using diluted acid pond subsequently into two-stage cleaning process
The acid and ferrous ion of steel tube surface wash away, and finally so that steel tube surface is formed one layer of uniform solvent membrane by solvent cell, then
Into in zinc-plated process；
Acid process be：
Concentrated hydrochloric acid is added to eo-acid pond, utilizes again after the solution use in eo-acid pond into the solution in old sour pond, old sour pond
Entering spent acid pond afterwards, spent acid pond enters diluted acid pond by the reuse dilute hydrochloric acid that low temperature distillation technology obtains and carries out two-stage cleaning,
Enter eo-acid pond after the solution use in diluted acid pond and concentrated hydrochloric acid configures eo-acid in proportion.
2. the zinc-plated pre-treating technology of steel pipe according to claim 1, it is characterised in that：The HCl concentration in eo-acid pond is maintained at
12%-18% when the sour Baume degrees when eo-acid pond reaches 30, is determined to be old sour pond, and the sour Baume degrees in old acid pond is greater than 40, and
It is determined as spent acid pond when detecting the acidity in acid less than 1, the acid in spent acid pond passes through 110 degrees Celsius of low temperature distillation technologies for dilute hydrochloric acid
It steams, the dilute hydrochloric acid steamed returns to reuse in diluted acid pond, obtains chlorine after the remaining liquid crystalization comprising frerrous chloride after distillation
Change ferrous solid.
3. the zinc-plated pre-treating technology of steel pipe according to claim 2, it is characterised in that：Diluted acid pond include diluted acid pond I and
Diluted acid pond II, steel pipe initially enter diluted acid pond I after coming out from eo-acid pond, and subsequently into diluted acid pond II, spent acid pond is distilled out
Reuse dilute hydrochloric acid enters diluted acid pond II.
4. the zinc-plated pre-treating technology of steel pipe according to claim 2, it is characterised in that：Online iron removal step is solvent from molten
It is passed through during sedimentation basin in agent pond through piping and carries out on-line mixing with hydrogen peroxide and ammonium hydroxide, control pH value in 4.8-5.0
Between, ferric hydroxide precipitate is formed, plate type pressure filter is then passed to and carries out filters pressing, filtered fluid, which returns in solvent cell to be formed to recycle, to be made
With, while obtaining filter cake i.e. solvent mud.
5. the zinc-plated pre-treating technology of steel pipe according to claim 2, it is characterised in that：It include 170~210g/ in solvent cell
The NH of L4The ZnCl of Cl, 210~250g/L2。
6. the zinc-plated pre-treating technology of steel pipe according to claim 4, it is characterised in that：The addition mole of hydrogen peroxide and ammonium hydroxide
Than being 1：4.
7. the zinc-plated pre-treating technology of steel pipe according to claim 4, it is characterised in that：Solvent and hydrogen peroxide and ammonium hydroxide are in pipe
The time mixed in road is no less than 3 minutes.
8. the zinc-plated pre-treating technology of steel pipe according to claim 4, it is characterised in that：Solvent mud is dissolved by spent acid, is added
Iron oxide black is converted into after alkali heating.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810862511.2A CN108914136B (en) | 2018-08-01 | 2018-08-01 | Steel pipe galvanizing pretreatment process |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810862511.2A CN108914136B (en) | 2018-08-01 | 2018-08-01 | Steel pipe galvanizing pretreatment process |
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| CN108914136A true CN108914136A (en) | 2018-11-30 |
| CN108914136B CN108914136B (en) | 2020-08-18 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108842130A (en) * | 2018-07-12 | 2018-11-20 | 中国航发哈尔滨轴承有限公司 | A method of it is modified to spherical roller surface using spherical roller thermo-chemical treatment special tooling |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204779769U (en) * | 2015-06-17 | 2015-11-18 | 北京钢研新冶精特科技有限公司 | Hot dip galvanization line |
-
2018
- 2018-08-01 CN CN201810862511.2A patent/CN108914136B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204779769U (en) * | 2015-06-17 | 2015-11-18 | 北京钢研新冶精特科技有限公司 | Hot dip galvanization line |
Non-Patent Citations (1)
| Title |
|---|
| 阎晓军: "《铁艺制作》", 28 February 2004, 黑龙江科学技术出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108842130A (en) * | 2018-07-12 | 2018-11-20 | 中国航发哈尔滨轴承有限公司 | A method of it is modified to spherical roller surface using spherical roller thermo-chemical treatment special tooling |
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| CN108914136B (en) | 2020-08-18 |
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