CN104529032A - Treatment method of hydrochloric acid waste liquid from steel pickling - Google Patents
Treatment method of hydrochloric acid waste liquid from steel pickling Download PDFInfo
- Publication number
- CN104529032A CN104529032A CN201410759103.6A CN201410759103A CN104529032A CN 104529032 A CN104529032 A CN 104529032A CN 201410759103 A CN201410759103 A CN 201410759103A CN 104529032 A CN104529032 A CN 104529032A
- Authority
- CN
- China
- Prior art keywords
- hydrochloride waste
- calcium
- calcium chloride
- rolled steel
- waste liquid
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Classifications
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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
- C02F9/00—Multistage treatment of water, waste water or sewage
-
- 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
- C02F1/02—Treatment of water, waste water, or sewage by heating
-
- 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
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
-
- 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
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/722—Oxidation by peroxides
-
- 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
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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
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/06—Controlling or monitoring parameters in water treatment pH
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2301/00—General aspects of water treatment
- C02F2301/08—Multistage treatments, e.g. repetition of the same process step under different conditions
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- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Treatment Of Water By Oxidation Or Reduction (AREA)
- Removal Of Specific Substances (AREA)
Abstract
The invention relates to the technical field of steel pickling waste liquid, and especially relates to a treatment method of hydrochloric acid waste liquid from steel pickling. The iron grade in the treated waste residue reaches 44-50% and can meet the requirements of steel mills on the iron grade quality, and a calcium chloride solution can meet the requirements of other enterprises. Zero pollution emission after hydrochloric acid waste liquid treatment is achieved, and resources are recycled. An oxidation neutralization method is improved and upgraded to enable liquid calcium, calcium chloride dihydrate, anhydrous calcium chloride and sludge produced after the treatment to meet the standard requirements and the industrial demands, so as to recycle the resources. The project investment is little, the treated products can be used in industrial production to both achieve zero emission of treated pollution wastes and recycle the resources, and moreover the operation cost is low, so that the treatment method is suitable for the development demands of small and medium-sized enterprises.
Description
Technical field
The present invention relates to acid washing rolled steel liquid waste disposal technique field, especially relate to a kind of hydrochloride waste treatment process of acid washing rolled steel.
Background technology
Pickling is that wire fabrication manufacturing enterprise is used for removing the very important operation of of steel surface oxide skin.Can produce a large amount of spent pickle liquors after acid washing rolled steel, China approximately will discharge nearly 1,000,000 tons of this type of waste hydrochloric acid liquor every year, and can increase along with the raising of steel output.The hydrogen ion of 0.05-0.5g/L and the ferrous ion of 60--250g/L is had, because serious corrodibility is put into " National Hazard refuse register " in waste hydrochloric acid.To hydrochloride waste if rationally do not processed, not only pollute environment but also waste valuable resource, the researchist of many enterprises has done a large amount of work for a long time in the reasonable treatment process of seeking spent pickle liquor and utilization ways both at home and abroad for this reason, is summed up and mainly contains hydrochlorate partition method, directly joins burning method, oxidation neutralisation etc.
Hydrochlorate partition method: waste hydrochloric acid liquor is after preheating, and enter titanium-palldium alloy evaporating pot and carry out heating evaporation, Separation and Recovery dilute hydrochloric acid, the raffinate in reactor can reclaim iron protochloride through decrease temperature crystalline.But the method needs several ten million investment, and titanium-palldium alloy equipment is domestic there is no processing technology, and working cost is higher, and medium-sized and small enterprises ability is not carried on the work and developed.
Direct spraying joins burning method: spray roasting process hydrochloride waste is that hydrochloride waste is squeezed into pre-concentration tower, and the waste heat circulation heating through stoving oven in tower is concentrated, makes it be vaporificly to spray in stoving oven from furnace roof portion by spray gun.Atomization hydrochloride waste is heated 500-600 degree Celsius and resolves into hydrogen chloride gas and iron protochloride in stove, and the latter is at high temperature changed into ferric oxide by the atmospheric oxygen entered in stove.Hydrogen chloride gas is separated from furnace roof through cyclonic separator, and the washing water being spray form by absorbing tower top absorb, and forms regeneration hydrochloric acid at the bottom of tower.The method needs the investment of more than one hundred million units, and need high-temperature heating equipment in operation, working cost is higher, is not suitable for operation and the development of medium-sized and small enterprises, and regeneration hydrochloric acid can not be used in acid cleaning process, easily causes new pollution.
Oxidation neutralisation: adopt the product calcium hydroxide of carbide slag digestion reaction to neutralize, after neutralization, pH value can reach requirement, but the calcium water produced, body refuse are difficult to reach standard-required and easily cause secondary pollution, the production technique of development improvement is needed to reclaim to make the liquid of generation and body refuse can reach commercial grade.
Summary of the invention
The object of the invention is to avoid the deficiencies in the prior art to provide a kind of hydrochloride waste treatment process of acid washing rolled steel, thus effectively solve the defect existed in prior art.
For achieving the above object, the technical scheme that the present invention takes is: the hydrochloride waste treatment process of described acid washing rolled steel, is characterized in comprising the following steps:
(1) by the hydrochloride waste after acid washing rolled steel by pump delivery to in the neutralizing well of agitator, start agitator, slowly add the acid hydrochloride waste pH value of carbide slag adjustment within the scope of 4-5, add superoxide uniformly, make the ferrous ion of in hydrochloride waste 40% be oxidized to ferric ion; Then blast air by air compressor and continue 5-6 hour, blast air and by boiler, the hydrochloride waste in neutralizing well is heated simultaneously, after being heated to 70-80 DEG C, keep 5-6 hour; Make to issue the black reaction of the pig iron in sufficient oxygen and 70-80 DEG C of temperature condition, i.e. Fe (OH) between ferrous ion compound wherein and ferric ion compound
2with Fe (OH)
3between react generate Fe
3o
4;
(2) filtered through plate and frame filter by reacted liquid, the content 44%-50% of iron in the body refuse produced after filtering, iron body refuse is through recycling;
(3) after filtering, limpid calcium chloride solution is through concentrated concentrate, when calcium contents is 30%, flows to sewage work for purifying sanitary sewage, flows to chemical enterprise for as refrigeration agent; When calcium contents is 40%, flow to petroleum drilling industry for carrying out kill-job operation; When calcium contents is 75%, as Snow Agent; When calcium contents is 95%, for the production of siccative and damp proof compound in the abrasive of dyestuff or industrial production.
Carbide slag in described first step is calcium hydroxide Ca (OH)
2, described superoxide is 30% oxydol H
2o
2, the add-on of described carbide slag measures the pH value of hydrochloride waste until controlled hydrochloride waste pH value reaches within the scope of 4-5 stops adding by pH value meter.
Concentrated concentrate in described third step refers to that the low levels calcium chloride solution pump that plate and frame filter is filtered out is squeezed in closed container, closed container is heated, bleed to closed container vacuum pump makes it be in subatmospheric environment simultaneously, the utilization that the boiling point reducing solution makes heat can reach maximum, evaporates the water vapour in solution thus the concentration of lifting calcium chloride solution in this approach.
The invention has the beneficial effects as follows: the hydrochloride waste treatment process of described acid washing rolled steel, its method for oxidation neutralisation carries out improveing, upgrading, produce calcium water after making process, Calcium dichloride dihydrate, Calcium Chloride Powder Anhydrous, body refuse can reach standard-required and industrial requirement to realize the recycling of resource.Project investment is few, product after process to be used in the middle of industrial production the zero release after not only achieving polluting waste process but also to achieve the recycling of resource and the development need of the not high applicable medium-sized and small enterprises of running cost.
Embodiment
Be described principle of the present invention and feature below, example, only for explaining the present invention, is not intended to limit scope of the present invention.
The hydrochloride waste treatment process of described acid washing rolled steel, is characterized in comprising the following steps:
(1) by the hydrochloride waste after acid washing rolled steel by pump delivery to in the neutralizing well of agitator, the amount of its hydrochloride waste is about 20-25 ton, start agitator, slowly add the acid hydrochloride waste pH value of carbide slag adjustment within the scope of 4-5, add superoxide 50-60Kg uniformly, make the ferrous ion of in hydrochloride waste 40% be oxidized to ferric ion; Then blast air by air compressor and continue 5-6 hour, blast air and by boiler, the hydrochloride waste in neutralizing well is heated simultaneously, after being heated to 70-80 DEG C, keep 5-6 hour; Make to issue the black reaction of the pig iron in sufficient oxygen and 70-80 DEG C of temperature condition, i.e. Fe (OH) between ferrous ion compound wherein and ferric ion compound
2with Fe (OH)
3between react generate Fe
3o
4;
(2) filtered through plate and frame filter by reacted liquid, the content 44%-50% of iron in the body refuse produced after filtering, iron body refuse is through recycling;
(3) after filtering, limpid calcium chloride solution is through concentrated concentrate, when calcium contents is 30%, flows to sewage work for purifying sanitary sewage, flows to chemical enterprise for as refrigeration agent; When calcium contents is 40%, flow to petroleum drilling industry for carrying out kill-job operation; When calcium contents is 75%, as Snow Agent; When calcium contents is 95%, for the production of siccative and damp proof compound in the abrasive of dyestuff or industrial production.Because filter after main component in solution be calcium chloride solution so 30%, 40% is measured by specific gravity hydrometer, proportion is 1.3,1.4 and reaches industry standard.75%, because calcium chloride is solid state when 95%, so determine content by carrying out bariumchloride titration after dissolution of solid.
Carbide slag in described first step is calcium hydroxide Ca (OH)
2, described superoxide is 30% oxydol H
2o
2, the add-on of described carbide slag measures the pH value of hydrochloride waste until controlled hydrochloride waste pH value reaches within the scope of 4-5 stops adding by pH value meter.
Concentrated concentrate in described third step refers to that the low levels calcium chloride solution pump that plate and frame filter is filtered out is squeezed in closed container, closed container is heated, bleed to closed container vacuum pump makes it be in subatmospheric environment simultaneously, the utilization that the boiling point reducing solution makes heat can reach maximum, evaporates the water vapour in solution thus the concentration of lifting calcium chloride solution in this approach.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (3)
1. a hydrochloride waste treatment process for acid washing rolled steel, is characterized in comprising the following steps:
(1) by the hydrochloride waste after acid washing rolled steel by pump delivery to in the neutralizing well of agitator, start agitator, slowly add the acid hydrochloride waste pH value of carbide slag adjustment within the scope of 4-5, add superoxide uniformly, make the ferrous ion of in hydrochloride waste 40% be oxidized to ferric ion; Then blast air by air compressor and continue 5-6 hour, blast air and by boiler, the hydrochloride waste in neutralizing well is heated simultaneously, after being heated to 70-80 DEG C, keep 5-6 hour; Make to issue the black reaction of the pig iron in sufficient oxygen and 70-80 DEG C of temperature condition, i.e. Fe (OH) between ferrous ion compound wherein and ferric ion compound
2with Fe (OH)
3between react generate Fe
3o
4;
(2) filtered through plate and frame filter by reacted liquid, the content 44%-50% of iron in the body refuse produced after filtering, iron body refuse is through recycling;
(3) after filtering, limpid calcium chloride solution is through concentrated concentrate, when calcium contents is 30%, flows to sewage work for purifying sanitary sewage, flows to chemical enterprise for as refrigeration agent; When calcium contents is 40%, flow to petroleum drilling industry for carrying out kill-job operation; When calcium contents is 75%, as Snow Agent; When calcium contents is 95%, for the production of siccative and damp proof compound in the abrasive of dyestuff or industrial production.
2. the hydrochloride waste treatment process of acid washing rolled steel as claimed in claim 1, is characterized in that: the carbide slag in described first step is calcium hydroxide Ca (OH)
2, described superoxide is 30% oxydol H
2o
2, the add-on of described carbide slag measures the pH value of hydrochloride waste until controlled hydrochloride waste pH value reaches within the scope of 4-5 stops adding by pH value meter.
3. the hydrochloride waste treatment process of acid washing rolled steel as claimed in claim 1, it is characterized in that: the concentrated concentrate in described third step refers to that the low levels calcium chloride solution pump that plate and frame filter is filtered out is squeezed in closed container, closed container is heated, bleed to closed container vacuum pump makes it be in subatmospheric environment simultaneously, the utilization that the boiling point reducing solution makes heat can reach maximum, evaporates the water vapour in solution thus the concentration of lifting calcium chloride solution in this approach.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410759103.6A CN104529032A (en) | 2014-12-15 | 2014-12-15 | Treatment method of hydrochloric acid waste liquid from steel pickling |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410759103.6A CN104529032A (en) | 2014-12-15 | 2014-12-15 | Treatment method of hydrochloric acid waste liquid from steel pickling |
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|---|---|
| CN104529032A true CN104529032A (en) | 2015-04-22 |
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ID=52844726
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| CN201410759103.6A Pending CN104529032A (en) | 2014-12-15 | 2014-12-15 | Treatment method of hydrochloric acid waste liquid from steel pickling |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105236493A (en) * | 2015-09-11 | 2016-01-13 | 厦门紫金矿冶技术有限公司 | Method for preparing hydroxyl iron oxide and semi-hydrated gypsum from acid metallurgical wastewater |
| CN105439345A (en) * | 2015-11-20 | 2016-03-30 | 扬州祥发资源综合利用有限公司 | Recycling method for removing lead from acid cleaning waste liquid of lead-containing steel wire ropes |
| CN106116004A (en) * | 2016-08-09 | 2016-11-16 | 天津正达科技有限责任公司 | A kind of steel hydrochloric acid pickling effluent resource reclaims and the processing method of zero-emission |
| CN106315651A (en) * | 2016-08-09 | 2017-01-11 | 天津正达科技有限责任公司 | Method for rapidly treating steel chlorohydric acid pickling waste liquid with assistance of microwaves |
| CN109264790A (en) * | 2018-10-25 | 2019-01-25 | 时文玲 | A method of ferroso-ferric oxide and calcium chloride are prepared using pickle liquor |
| CN113087204A (en) * | 2021-03-26 | 2021-07-09 | 同济大学 | Resourceful treatment method for treating waste acid containing iron and zinc |
| CN115417442A (en) * | 2022-09-23 | 2022-12-02 | 浙江佳境环保科技有限公司 | Calcium chloride regeneration system |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105236493A (en) * | 2015-09-11 | 2016-01-13 | 厦门紫金矿冶技术有限公司 | Method for preparing hydroxyl iron oxide and semi-hydrated gypsum from acid metallurgical wastewater |
| CN105439345A (en) * | 2015-11-20 | 2016-03-30 | 扬州祥发资源综合利用有限公司 | Recycling method for removing lead from acid cleaning waste liquid of lead-containing steel wire ropes |
| CN106116004A (en) * | 2016-08-09 | 2016-11-16 | 天津正达科技有限责任公司 | A kind of steel hydrochloric acid pickling effluent resource reclaims and the processing method of zero-emission |
| CN106315651A (en) * | 2016-08-09 | 2017-01-11 | 天津正达科技有限责任公司 | Method for rapidly treating steel chlorohydric acid pickling waste liquid with assistance of microwaves |
| CN109264790A (en) * | 2018-10-25 | 2019-01-25 | 时文玲 | A method of ferroso-ferric oxide and calcium chloride are prepared using pickle liquor |
| CN113087204A (en) * | 2021-03-26 | 2021-07-09 | 同济大学 | Resourceful treatment method for treating waste acid containing iron and zinc |
| CN115417442A (en) * | 2022-09-23 | 2022-12-02 | 浙江佳境环保科技有限公司 | Calcium chloride regeneration system |
| CN115417442B (en) * | 2022-09-23 | 2023-09-22 | 浙江佳境环保科技有限公司 | Calcium chloride regeneration system |
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Application publication date: 20150422 |