CN110002567A - A kind of method that stainless steel annealing pickling waste waters neutralizes and sludge is applied flexibly - Google Patents
A kind of method that stainless steel annealing pickling waste waters neutralizes and sludge is applied flexibly Download PDFInfo
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- CN110002567A CN110002567A CN201910220048.6A CN201910220048A CN110002567A CN 110002567 A CN110002567 A CN 110002567A CN 201910220048 A CN201910220048 A CN 201910220048A CN 110002567 A CN110002567 A CN 110002567A
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- waste waters
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/58—Treatment of water, waste water, or sewage by removing specified dissolved compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/12—Treatment of sludge; Devices therefor by de-watering, drying or thickening
- C02F11/121—Treatment of sludge; Devices therefor by de-watering, drying or thickening by mechanical de-watering
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/16—Nitrogen compounds, e.g. ammonia
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/16—Nature of the water, waste water, sewage or sludge to be treated from metallurgical processes, i.e. from the production, refining or treatment of metals, e.g. galvanic wastes
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2305/00—Use of specific compounds during water treatment
- C02F2305/02—Specific form of oxidant
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
Abstract
The invention discloses the method that a kind of neutralization of stainless steel annealing pickling waste waters and sludge are applied flexibly, include the following steps: that middle predetermined value pH is arranged1=X, pH2=Y；Milk of lime is added to pickling waste waters, pickling waste waters pH value is made to reach middle predetermined value pH1, addition flocculant stirring standing；The waste water obtained to above-mentioned steps continues to add milk of lime, and sour pH value of waste water is made to reach middle predetermined value pH2Stop addition milk of lime, replaced with sodium hydrate aqueous solution, until neutralizing terminal pH=10.5, addition flocculant stirring is stood.The beneficial effects of the invention are as follows realize sludge classification precipitating using fractional neutralization method by control pH value, CaO is not put into excessively, reduce denitrogenation processing cost, guarantee Chinese effluent index, differential recycling is realized for the ingredient properties of fractional neutralization product, and economic maximization effect is realized under the premise of safety and environmental protection.
Description
Technical field
The invention belongs to solid liquid waste resource recycling fields in stainless steel production more particularly to a kind of stainless steel to move back
The sludge obtained after fiery pickling waste waters neutralization method and neutralization applies flexibly method.
Background technique
Stainless steel is widely used because of its excellent corrosion resistance and good appearance.Stainless steel in process of production,
Inevitably pass through the process such as annealing, normalizing, quenching, welding, surface can generate the oxide skin of black often.Oxidation
Skin not only influences the presentation quality of stainless steel, can also have an adverse effect to the following process of product, therefore must before following process
It must be removed using surface treatment methods such as pickling, polishings.Acid-washing stainless steel process is removed with sulfuric acid pre-sour first
The iron scale on surface is removed, then carries out pickling with nitric acid and hydrofluoric acid nitration mixture.Nitric acid with strong oxidizing property can be by metal
And metal oxide, generate Cr3+、 Fe3+And Ni2+Ion, these metal ions and hydrofluoric acid react, and generate
Solvable or indissoluble metal fluoride.With the progress of acid cleaning process, the nitric acid and hydrofluoric acid to dissociate in pickling solution is fewer and fewer,
Reaction product is more and more.When metal salt crystallizes precipitation from pickling solution in pickling solution, descaling bath must be cleaned or replaced.One
Since straight, the processing of a large amount of pickling waste waters generated in producing stainless steel process is the problem of iron and steel enterprise.With steel and iron industry
Gradually develop, people gradually recognize that pickling waste waters is especially the harm to mankind itself to environment, in addition environmental protection is to useless
Water discharge has strict requirements, first must be by its harmless treatment.The processing for the pickling waste waters that acid-washing stainless steel generates is compared
Complexity, there are mainly two types of thinkings at present: first is that exploring the dirt of generation after stainless steel acid cleaning waste water is neutralized using traditional lime
The administering method of mud；Second is that exploring the method for directly administering stainless steel acid cleaning waste water.Most economical efficient mode is exactly traditional
By the neutralisation in addition quick lime with residual acid in waste water, the flocculation sedimentation of metal hydroxides is realized, finally by filters pressing
Form the lower neutralization sludge of water content.In the prior art in order to guarantee effluent index after neutralizing, the mode for taking a step to neutralize,
It is put into pickling waste waters a large amount of calcium oxide (CaO), Ca ion concentration is high in water, and obtained sludge quantity is big.Neutralize obtained dirt
There are two types of the processing scheme of mainstream, landfill and electric furnace reuses at present for mud.Because hydrofluoric acid is that stainless steel realizes that continuous acid-washing is most heavy
The ingredient wanted, so fluorine content is very high in and in the sludge of generation.Fluorine-containing sludge directly fill be to soil it is harmful, easily
It is absorbed by plants, and then constitutes a threat to plant growth and human health, and the heavy metal in sludge is easy polluted underground water,
So fluorine-containing and metal sludge must select special landfill at present, but expensive, the long processing period of special landfill, sludge
The metal of middle recoverable also directly wastes, so many enterprises start to select in electric furnace reuse and sludge.Same fluorine-containing dirt
When mud investment electric furnace carries out smelting operation, it can be inhaled into flue, the hydrofluoric acid generated under hot conditions generates corrosion to water-cooling wall,
Leak occurs, electric furnace maintenance cycle serious curtailment, maintenance cost is expensive, influences rhythm of production and has risk.In addition, investment
A large amount of calcium oxide (CaO) neutralizing acid waste water will cause water outlet Ca ion concentration while removing metal ion and be significantly increased, directly
Connecing influences subsequent denitrogenation water process, increases denitrogenation period and cost.
Summary of the invention
In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide a kind of stainless steel annealing pickling waste waters neutralize and
The method that sludge is applied flexibly, solves the problems, such as in annealing and pickling waste water and medicament calcium oxide (CaO) input amount is excessive；Solve water outlet calcium from
Sub- concentration height influences the problem of nitric efficiency；Solve the problems, such as that sludge precious metal recycles；Solve applying flexibly for fluorine-containing sludge
Problem.
To achieve the above object, the present invention adopts the following technical scheme:
A kind of method that stainless steel annealing pickling waste waters neutralizes, its main feature is that including the following steps: stainless steel annealing pickling
Waste water carries out fractional neutralization, and middle predetermined value pH is arranged1=X, pH2=Y；Mud, water separate for the first time, and stone is added into pickling waste waters
Grey cream, makes pickling waste waters pH value reach middle predetermined value pH1, flocculant is added, stirring is stood, and obtains primary sludge and primary useless
Water；The working principle of the step is that neutralization reaction is arranged according to nitric acid, hydrofluoric acid and concentration of metal ions in pickling waste waters
Corresponding pH value (X), fluorinion in waste water is present in sludge with precipitation form, and precious metal ion exists with free state
In Yu Yici waste water, and task is separated for the first time by adding appropriate flocculant and control stirring time of repose completion mud, water；Institute
Primary sludge is stated for stainless steel smelting auxiliary material；
Mud, water secondary separation continue to add milk of lime into the waste water that above-mentioned steps obtain, reach sour pH value of waste water
To middle predetermined value pH2Stop addition milk of lime, replaced with sodium hydroxide (NaOH) aqueous solution, until neutralizing terminal pH=
10.5, flocculant is added, stirring is stood, and obtains secondary sludge and secondary wastewater；The working principle of the step is anti-by neutralizing
Should realize precious metal ion flocculation, precipitating, formed secondary sludge, while in order to reduce water outlet denitrogenation processing efficiency and at
This, needs to add appropriate NaOH aqueous solution and completes neutralization reaction；The secondary sludge carries out precious metal recycling.
Further, the value range of the X is 4.5-5.0.
Further, the value range of the Y is 8.0-8.5.
Further, the primary sludge includes pressing the primary sludge for the step of stainless steel smelting auxiliary material
Filter carries out pressure ball after mixing with electric stove dust ash, molasses on ball press, and the reuse of stainless steel smelting auxiliary material is used as after baking.
Further, the step of secondary sludge progress precious metal recycling includes pressing the secondary sludge
Filter, mixes with electric stove dust ash, restores to obtain precious metal by mineral hot furnace.
Further, the secondary wastewater carries out denitrogenation processing.
Further, the processing step is suitable for the processing of hot-rolled stainless steel annealing and pickling waste water.
Compared with prior art, the beneficial effects of the present invention are: pickling waste waters is neutralized through control pH value using in substep
Sludge classification precipitating is realized with method, CaO is not put into excessively, reduces denitrogenation processing cost, not only guarantees that water outlet meets discharge index,
Differential recycling more importantly is realized for the ingredient properties of fractional neutralization product, reduces stainless steel smelting equipment
Corrosion risk will not adversely affect rhythm of production and equipment, significantly reduce maintenance cost, before safety and environmental protection
The economic maximization effect of realization is put, while also achieving metal in sludge effective recycling.
Specific embodiment
The present invention will be further described combined with specific embodiments below.
A kind of method that stainless steel annealing pickling waste waters neutralizes, its main feature is that including the following steps: stainless steel annealing pickling
Waste water carries out fractional neutralization, and middle predetermined value pH is arranged1The value range of=X, X are 4.5-5.0； pH2The value range of=Y, Y
It is 8.0-8.5；Mud, water separate for the first time, and milk of lime is added into pickling waste waters, and pickling waste waters pH value is made to reach middle predetermined value
pH1, flocculant is added, stirring is stood, and obtains primary sludge and a waste water；The working principle of the step is according to pickling waste waters
Middle nitric acid, hydrofluoric acid and concentration of metal ions are arranged the corresponding pH value of neutralization reaction (X), by fluorinion in waste water to precipitate
Form is present in sludge, and precious metal ion is present in a waste water with free state, and by adding appropriate flocculant
And control stirring time of repose completes mud, water separates task for the first time；The primary sludge is used for stainless steel smelting auxiliary material；Once
Sludge includes that the primary sludge is carried out filters pressing for the step of stainless steel smelting auxiliary material, is mixed with electric stove dust ash, molasses
Afterwards, pressure ball is carried out on ball press, and the reuse of stainless steel smelting auxiliary material is used as after baking；
Mud, water secondary separation continue to add milk of lime into the waste water that above-mentioned steps obtain, reach sour pH value of waste water
To middle predetermined value pH2Stop addition milk of lime, replaced with sodium hydroxide (NaOH) aqueous solution, until neutralizing terminal pH=
10.5, flocculant is added, stirring is stood, and obtains secondary sludge and secondary wastewater；The working principle of the step is anti-by neutralizing
Should realize precious metal ion flocculation, precipitating, formed secondary sludge, while in order to reduce water outlet denitrogenation processing efficiency and at
This, needs to add appropriate NaOH aqueous solution and completes neutralization reaction；The secondary sludge carries out precious metal recycling；Secondary sludge into
The step of row precious metal recycles includes that the secondary sludge is carried out filters pressing, is mixed with electric stove dust ash, also by mineral hot furnace
Original obtains precious metal；The secondary wastewater that mud, water secondary separation are obtained carries out denitrogenation processing.
Above-mentioned processing step is suitable for the processing of hot-rolled stainless steel annealing and pickling waste water.
The principles and effects of the invention, and the implementation that part uses only is illustrated in the above embodiments
Example, and is not intended to limit the present invention；It should be pointed out that for those of ordinary skill in the art, not departing from wound of the present invention
Under the premise of making design, various modifications and improvements can be made, and these are all within the scope of protection of the present invention.
Claims (7)
1. a kind of method that stainless steel annealing pickling waste waters neutralizes and sludge is applied flexibly, characterized by the following steps: stainless
Steel annealing and pickling waste water carries out fractional neutralization, and middle predetermined value pH is arranged1=X, pH2=Y；Mud, water separate for the first time, useless to pickling
Milk of lime is added in water, and sour pH value of waste water is made to reach middle predetermined value pH1, flocculant is added, stirring is stood, and obtains primary sludge
With a waste water；The primary sludge is used as stainless steel smelting auxiliary material；
Mud, water secondary separation continue to add milk of lime into the waste water that above-mentioned steps obtain, and make during sour pH value of waste water reaches
Between preset value pH2Stop addition milk of lime, is replaced with sodium hydrate aqueous solution, until terminal pH=10.5 is neutralized, addition flocculation
Agent, stirring are stood, and obtain secondary sludge and secondary wastewater；The secondary sludge is subjected to precious metal recycling.
A kind of method that 2. stainless steel annealing pickling waste waters neutralizes according to claim 1 and sludge is applied flexibly, it is characterised in that:
The value range of the X is 4.5-5.0.
A kind of method that 3. stainless steel annealing pickling waste waters neutralizes according to claim 1 and sludge is applied flexibly, it is characterised in that:
The value range of the Y is 8.0-8.5.
A kind of method that 4. stainless steel annealing pickling waste waters neutralizes according to claim 1 and sludge is applied flexibly, it is characterised in that:
The primary sludge be used as stainless steel smelting auxiliary material the step of include by the primary sludge carry out filters pressing, with electric stove dust ash,
After molasses mixing, pressure ball is carried out on ball press, and the reuse of stainless steel smelting auxiliary material is used as after baking.
A kind of method that 5. stainless steel annealing pickling waste waters neutralizes according to claim 1 and sludge is applied flexibly, it is characterised in that:
The step of secondary sludge progress precious metal recycling includes that the secondary sludge is carried out filters pressing, mixed with electric stove dust ash
It closes, restores to obtain precious metal by mineral hot furnace.
A kind of method that 6. stainless steel annealing pickling waste waters neutralizes according to claim 1 and sludge is applied flexibly, it is characterised in that:
The secondary wastewater carries out denitrogenation processing.
7. any one of -4 method that a kind of stainless steel annealing pickling waste waters neutralizes and sludge is applied flexibly according to claim 1,
Be characterized in that: the processing step is suitable for the processing of hot-rolled stainless steel annealing and pickling waste water.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110317951A (en) * | 2019-07-16 | 2019-10-11 | 嘉善助远再生资源回收有限公司 | A method of nichrome is produced using dedusting ash of stainless steel and pickling sludge |
| CN111850233A (en) * | 2020-07-31 | 2020-10-30 | 阴通明 | Recovery process of stainless steel pickling residues |
| CN112358206A (en) * | 2020-11-16 | 2021-02-12 | 山西太钢不锈钢股份有限公司 | Method for improving activity of blast furnace slag micro powder |
| CN113429030A (en) * | 2021-08-11 | 2021-09-24 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for cooperatively treating sintering desulfurization acid wastewater and machine head dedusting ash |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110317951A (en) * | 2019-07-16 | 2019-10-11 | 嘉善助远再生资源回收有限公司 | A method of nichrome is produced using dedusting ash of stainless steel and pickling sludge |
| CN111850233A (en) * | 2020-07-31 | 2020-10-30 | 阴通明 | Recovery process of stainless steel pickling residues |
| CN112358206A (en) * | 2020-11-16 | 2021-02-12 | 山西太钢不锈钢股份有限公司 | Method for improving activity of blast furnace slag micro powder |
| CN113429030A (en) * | 2021-08-11 | 2021-09-24 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for cooperatively treating sintering desulfurization acid wastewater and machine head dedusting ash |
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