CN116356156A - Harmless treatment method of sulfuric acid cinder - Google Patents
Harmless treatment method of sulfuric acid cinder Download PDFInfo
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- CN116356156A CN116356156A CN202310378347.9A CN202310378347A CN116356156A CN 116356156 A CN116356156 A CN 116356156A CN 202310378347 A CN202310378347 A CN 202310378347A CN 116356156 A CN116356156 A CN 116356156A
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- sulfuric acid
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B19/00—Obtaining zinc or zinc oxide
- C22B19/30—Obtaining zinc or zinc oxide from metallic residues or scraps
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B13/00—Obtaining lead
- C22B13/02—Obtaining lead by dry processes
- C22B13/025—Recovery from waste materials
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B19/00—Obtaining zinc or zinc oxide
- C22B19/20—Obtaining zinc otherwise than by distilling
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
- C22B7/001—Dry processes
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
- C22B7/04—Working-up slag
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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Abstract
The invention relates to the technical field of metallurgy, in particular to a method for innocent treatment of sulfuric acid cinder. The method comprises the following steps: (1) mixing ingredients: mixing the sulfuric acid cinder, the blast furnace gas ash, the sintering electric field ash and the coking dust to form a mixture; (2) rotary kiln charging roasting: feeding the mixture obtained in the step (1) to a rotary kiln feeding chamber for feeding, and then rolling, moving and roasting the mixture in the kiln; (3) cooling and collecting: cooling flue gas generated by roasting, and then entering a dust collection system to collect zinc suboxide, lead oxide and the like; the furnace burden after roasting is iron slag. According to the invention, the technical processes of extracting zinc, lead and the like by adopting a rotary kiln fire method reduction method are adopted, so that harmful impurities are reduced, harmful elements are effectively reduced, the purpose of harmless recycling is achieved, the comprehensive utilization of solid wastes is realized, and waste materials are changed into valuable materials.
Description
Technical Field
The invention relates to the technical field of metallurgy, in particular to a method for innocent treatment of sulfuric acid cinder.
Background
The pyrite acid making process is a traditional sulfuric acid making process, and the main component of the sulfuric acid cinder discharged in the acid making process is ferric oxide, and meanwhile, the pyrite acid making process contains oxide impurities of metals such as zinc, lead and the like. The discharged sulfuric acid cinder can be used as an iron-making raw material; however, because metallic impurities such as zinc and lead can have a great influence on the blast furnace, wherein zinc element can deteriorate the gas permeability of the furnace charge, destroy the gas distribution, cause the gas distribution to be disordered, and the furnace charge is difficult to descend, so that the blast furnace is difficult to collapse, slide and even suspend, the zinc element enters slag-iron liquid or infiltrates into refractory materials of a furnace wall of a furnace lining to gradually form furnace tumors, the blast furnace is destroyed to move forward, the zinc element is attached to a cooling wall in a slag skin form, and the slag skin formed by taking zinc as a binder is extremely unstable and easy to cause frequent falling, so that the furnace temperature fluctuates; the lead element can also cause the problems of floating of a brick layer, damage of a furnace bottom brickwork, cracking of a furnace shell, blockage of a skimming tool and the like.
A method for extracting valuable metals from gold-bearing sulfuric acid cinder and performing innocent treatment (application number: CN 201711158249.5) discloses a method for extracting valuable metals from gold-bearing sulfuric acid cinder and performing innocent treatment, and specifically, by a chloridizing roasting mode, a chloridizing agent can be used for chloridizing some metals into easily-dissolved, easily-volatilized and easily-floated chlorides at high temperature.
At present, in order to obtain qualified iron pellets, lignite or a mixture of lignite and coke powder is mainly added as a reducing agent to perform medium-temperature reduction roasting, and a chlorinating agent is used to perform high-temperature chlorination roasting to volatilize impurity metal elements. However, the existing method requires additional raw materials such as lignite, chlorinating agent and the like, and has high treatment cost and complex process.
Disclosure of Invention
Aiming at the problems of high treatment cost and complex process of the prior art, the invention provides a harmless treatment method of the sulfuric acid cinder.
The technical scheme of the invention is as follows:
a harmless treatment method of sulfuric acid cinder comprises the following steps:
(1) Mixing and proportioning: mixing the sulfuric acid cinder, the blast furnace gas ash, the sintering electric field ash and the coking dust to form a mixture;
(2) And (3) charging and roasting in a rotary kiln: feeding the mixture obtained in the step (1) to a rotary kiln feeding chamber for feeding, and then rolling, moving and roasting the mixture in the kiln;
(3) And (3) cooling and collecting: cooling flue gas generated by roasting, and then entering a dust collection system to collect zinc suboxide, lead oxide and the like; and the roasted furnace burden is iron slag, and is discharged from the kiln head, and slag iron is selected and returned to the sintering burden for use.
Further, blast furnace gas ash, sintering electric field ash and coking dust in the step (1) are solid wastes generated in the steel smelting process, and metal oxides such as zinc oxide, lead oxide and the like in the sulfuric acid cinder are reduced by a rotary kiln fire reduction technology process.
Further, the components of the sulfuric acid cinder in the step (1) comprise Fe in percentage by mass 2 O 3 :85%-89%,SiO 2 :1.8%-3.7%,ZnO:2.8%-4%,SO 3 :1.4%-3.5%,PbO:1.7%-1.9%,CuO:0.9%-1.5%,MnO:0.19%-0.21%,As 2 O 3 :0.4%-0.56%,Al 2 O 3 :0.29% -0.72% and the balance of unavoidable impurities.
Further, in the step (1), the mass ratio of the sulfuric acid cinder is 15% -20%, the mass ratio of the blast furnace gas ash is 35% -40%, the mass ratio of the sintering power plant ash is 15% -20%, and the mass ratio of the coking dust removal ash is 20% -30%.
Further, the roasting process in the step (2) is divided into three sections of preheating, roasting reaction and cooling; the kiln material is heated rapidly in the kiln tail preheating section, the oxides in the mixture are reduced into vapors of zinc, lead and the like by carbon or carbon monoxide in the roasting reaction stage, the vapors enter a gas phase state, and enter a flue gas cooling section from the kiln tail along with the gas flow in the kiln, and the vapors are oxidized into oxides along with the increase of oxygen in the atmosphere.
Further, the preheating temperature is 650-850 ℃, the roasting reaction temperature is 1100-1250 ℃, and the kiln head cooling temperature is 850-900 ℃.
Further, flue gas generated by roasting enters a U-shaped cooling pipe from the kiln tail for further cooling, zinc suboxide, lead oxide and the like become solid, enter a cloth bag dust collection chamber for completing product collection, and the waste gas is subjected to desulfurization treatment by an induced draft fan and then is discharged after reaching standards.
Further, the roasted furnace burden is iron slag, is discharged from the kiln head, enters a water cooling tank for rapid cooling, and is selected and returned to the sintering burden for use.
Further, the content of zinc in the selected slag iron is less than or equal to 0.5 percent, and the content of lead is less than or equal to 0.1 percent.
Furthermore, the rotary kiln has no abnormal phenomena such as ring formation and the like.
Further, the rotary kiln has a size of phi 3.3×52m, and a rotary hearth furnace can be used instead of the rotary kiln.
The invention has the beneficial effects that: the invention utilizes the solid wastes such as blast furnace gas ash, sintering electric field ash, coking dust and the like generated in the steel smelting process, reduces zinc oxide, lead oxide and the like in the sulfuric acid cinder by adopting the technical processes such as rotary kiln pyrogenic reduction and zinc extraction, lead oxide and the like, realizes the comprehensive utilization of the solid wastes, and changes waste into valuable. The oxygen in the air is directly utilized for oxidation in the treatment process of impurity metal elements such as zinc, lead and the like, and the process is simpler without independently adding materials. The abnormal conditions such as loop formation and the like are not found in the mixing proportion provided by the invention, and the effect of removing zinc and lead is good. The mixture of zinc suboxide, lead oxide and the like obtained by cooling the flue gas has certain economic value and can realize the reutilization of impurity metals.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the description of the embodiments or the prior art will be briefly described below, and it will be obvious to those skilled in the art that other drawings can be obtained from these drawings without inventive effort.
Fig. 1 is a process flow diagram of the present invention.
Detailed Description
In order to make the technical solution of the present invention better understood by those skilled in the art, the technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.
The rotary kiln used in the following examples is a rotary kiln with phi 3.3 multiplied by 52m, blast furnace gas ash, sintering electric field ash and coking dust removal ash are all solid wastes generated in the steel smelting process, and the blast furnace gas ash comprises the following chemical components in percentage by mass: 35.8%, P:0.074%, siO 2 :5.88%,S:0.44%,Al 2 O 3 :3.49%,TiO 2 :0.146%,MnO:0.163%,CaO:2.8%,MgO:0.651%,Pb:0.016%,Zn:0.635%,Na 2 O:0.171%,K 2 O:0.271%, cl:5.82%, the balance C, O and other unavoidable impurities; the sintered power plant ash comprises the following chemical components in percentage by mass: 34.41%, P:0.092%, siO 2 :4.68%,S:0.078%,Al 2 O 3 :1.48%,TiO 2 :0.114%,MnO:0.395%,CaO:8.46%,MgO:2.01%,Pb:0.593%,Zn:0.095%,Na 2 O:1.63%,K 2 O:11.53%, cl:10.63%, the balance C, O and other unavoidable impurities; carbon content of coked dust>60%。
Example 1
(1) According to the sulfuric acid cinder: blast furnace gas ash: sintering electric field ash: the coking dust removal ash mass ratio=3:7:3:5 is used for preparing a mixture, and the chemical components of the sulfuric acid cinder are as follows: fe (Fe) 2 O 3 :89%,SiO 2 :1.8%,ZnO:2.8%,SO 3 :1.4%,PbO:1.8%,CuO:0.9%,MnO:0.19%,As 2 O 3 :0.43%,Al 2 O 3 :0.56% and the balance of unavoidable impurities;
(2) Conveying the mixture to a charging chamber of a rotary kiln, preheating the mixture from the kiln tail of the rotary kiln, rolling the mixture in the kiln to fully bake, reducing oxides in the mixture by carbon or carbon monoxide to zinc, lead and other vapors in a roasting reaction stage, entering a gas phase state, entering a flue gas cooling section from the kiln tail along with the gas flow in the kiln, and oxidizing the oxides along with the increase of oxygen in the atmosphere; the temperature in the preheating stage is 700 ℃, the temperature in the roasting reaction stage in the kiln is 1200 ℃, and the cooling temperature of the kiln head is 850 ℃;
(3) Flue gas generated by roasting enters a U-shaped cooling pipe from the kiln tail for cooling, becomes solid zinc suboxide, lead oxide and the like, and reaches the collection in a cloth bag dust collection chamber for collection, and the waste gas is discharged after desulfurization treatment of the waste gas reaches the standard through a draught fan; discharging the roasted furnace burden from the kiln head, entering a water cooling tank for rapid cooling, and selecting slag iron;
the detection shows that the content of zinc in the slag iron is 0.3256 percent and the content of lead is 0.0775 percent.
Example 2
(1) According to the sulfuric acid cinder: blast furnace gas ash: sintering electric field ash: the coking dust removal ash mass ratio=1:2:1:1 is used for preparing a mixture, and the chemical components of the sulfuric acid cinder are as follows: fe (Fe) 2 O 3 :87%,SiO 2 :2.3%,ZnO:3.2%,SO 3 :1.7%,PbO:1.8%,CuO:1.2%,MnO:0.19%,As 2 O 3 :0.43%,Al 2 O 3 :0.56% and the balance of unavoidable impurities;
(2) Conveying the mixture to a charging chamber of a rotary kiln, preheating the mixture from the kiln tail of the rotary kiln, rolling the mixture in the kiln to fully bake, reducing oxides in the mixture by carbon or carbon monoxide to zinc, lead and other vapors in a roasting reaction stage, entering a gas phase state, entering a flue gas cooling section from the kiln tail along with the gas flow in the kiln, and oxidizing the oxides along with the increase of oxygen in the atmosphere; the temperature of the preheating stage is 800 ℃, the temperature of the roasting reaction stage in the kiln is 1250 ℃, and the cooling temperature of the kiln head is 875 ℃;
(3) Flue gas generated by roasting enters a U-shaped cooling pipe from the kiln tail for cooling, becomes solid zinc suboxide, lead oxide and the like, and reaches the collection in a cloth bag dust collection chamber for collection, and the waste gas is discharged after desulfurization treatment of the waste gas reaches the standard through a draught fan; discharging the roasted furnace burden from the kiln head, entering a water cooling tank for rapid cooling, and selecting slag iron;
the detection shows that the content of zinc in the slag iron is 0.4726 percent and the content of lead is 0.0865 percent.
Comparative example 1
(1) According to the sulfuric acid cinder: blast furnace gas ash: sintering electric field ash: the coking dust removal ash mass ratio=4:7:3:5 is used for preparing the mixture, and the chemical components of the sulfuric acid cinder are as follows: fe (Fe) 2 O 3 :89%,SiO 2 :1.8%,ZnO:2.8%,SO 3 :1.4%,PbO:1.8%,CuO:0.9%,MnO:0.19%,As 2 O 3 :0.43%,Al 2 O 3 :0.56%, the rest unavoidable impurities;
(2) Conveying the mixture to a charging chamber of a rotary kiln, preheating the mixture from the kiln tail of the rotary kiln, rolling the mixture in the kiln to fully bake, reducing oxides in the mixture by carbon or carbon monoxide to zinc, lead and other vapors in a roasting reaction stage, entering a gas phase state, entering a flue gas cooling section from the kiln tail along with the gas flow in the kiln, and oxidizing the oxides along with the increase of oxygen in the atmosphere; the temperature in the preheating stage is 700 ℃, the temperature in the roasting reaction stage in the kiln is 1200 ℃, and the cooling temperature of the kiln head is 850 ℃;
(3) Flue gas generated by roasting enters a U-shaped cooling pipe from the kiln tail for cooling, becomes solid zinc suboxide, lead oxide and the like, and reaches the collection in a cloth bag dust collection chamber for collection, and the waste gas is discharged after desulfurization treatment of the waste gas reaches the standard through a draught fan; discharging the roasted furnace burden from the kiln head, entering a water cooling tank for rapid cooling, and selecting slag iron;
the detection shows that the content of zinc in the slag iron is 0.5256 percent and the content of lead is 0.1078 percent.
The slag iron obtained in the embodiment 1-2 is used for sintering the ingredients, so that normal production can be realized; no abnormal condition is found in the production process of the embodiment 1-2, and the effect of removing zinc and lead is better; the rotary kiln of comparative example 1 has slight ring formation, and has slightly poorer zinc and lead removal effects.
Although the present invention has been described in detail by way of preferred embodiments with reference to the accompanying drawings, the present invention is not limited thereto. Various equivalent modifications and substitutions may be made in the embodiments of the present invention by those skilled in the art without departing from the spirit and scope of the present invention, and it is intended that all such modifications and substitutions be within the scope of the present invention/be within the scope of the present invention as defined by the appended claims.
Claims (10)
1. The harmless treatment method of the sulfuric acid cinder is characterized by comprising the following steps of:
(1) Mixing and proportioning: mixing the sulfuric acid cinder, the blast furnace gas ash, the sintering electric field ash and the coking dust to form a mixture;
(2) And (3) charging and roasting in a rotary kiln: feeding the mixture obtained in the step (1) to a rotary kiln feeding chamber for feeding, and then rolling, moving and roasting the mixture in the kiln;
(3) And (3) cooling and collecting: cooling flue gas generated by roasting, and then entering a dust collection system to collect zinc suboxide and lead oxide; the furnace burden after roasting is iron slag.
2. The method for innocent treatment of sulfuric acid cinder according to claim 1, wherein the blast furnace gas ash, the sintering electric field ash and the coking dust ash in the step (1) are solid wastes generated in the steel smelting process.
3. The method for innocent treatment of sulfuric acid residues according to claim 1, wherein the components of the sulfuric acid residues in the step (1) comprise Fe in percentage by mass 2 O 3 :85%-89%,SiO 2 :1.8%-3.7%,ZnO:2.8%-4%,SO 3 :1.4%-3.5%,PbO:1.7%-1.9%,CuO:0.9%-1.5%,MnO:0.19%-0.21%,As 2 O 3 :0.4%-0.56%,Al 2 O 3 :0.29% -0.72% and the balance of unavoidable impurities.
4. The method for innocent treatment of sulfuric acid cinder, as claimed in claim 1, wherein in the step (1), the mass ratio of the sulfuric acid cinder is 15% -20%, the mass ratio of blast furnace gas ash is 35% -40%, the mass ratio of sintering power plant ash is 15% -20%, and the mass ratio of coking dust is 20% -30%.
5. The method for innocent treatment of sulfuric acid cinder according to claim 1, wherein the roasting process in the step (2) is divided into three sections of preheating, roasting reaction and cooling.
6. The method for innocent treatment of sulfuric acid cinder according to claim 5, wherein the preheating temperature is 650-850 ℃, the roasting reaction temperature is 1100-1250 ℃ and the cooling temperature is 850-900 ℃.
7. The method for innocent treatment of the sulfuric acid cinder according to claim 1, wherein flue gas generated by roasting is discharged after being cooled by a U-shaped pipe, collected by a cloth bag dust collecting chamber and subjected to desulfurization treatment to reach standards.
8. The method for innocent treatment of sulfuric acid cinder according to claim 1, wherein the roasted furnace burden is discharged from a kiln head and enters a water cooling tank for rapid cooling, and the iron slag is selected.
9. The method for innocent treatment of sulfuric acid cinder as defined in claim 8, wherein the content of zinc in the selected cinder iron is less than or equal to 0.5% and the content of lead is less than or equal to 0.1%.
10. The method for innocuous treatment of sulfuric acid cinder as defined in claim 1, wherein the selected cinder iron is returned to the sintering batch.
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