CN109321752B - Method for preparing regenerated iron particles by using metal surface treatment waste - Google Patents
Method for preparing regenerated iron particles by using metal surface treatment waste Download PDFInfo
- Publication number
- CN109321752B CN109321752B CN201811314336.XA CN201811314336A CN109321752B CN 109321752 B CN109321752 B CN 109321752B CN 201811314336 A CN201811314336 A CN 201811314336A CN 109321752 B CN109321752 B CN 109321752B
- Authority
- CN
- China
- Prior art keywords
- waste
- surface treatment
- metal surface
- chromium
- acid
- 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.)
- Active
Links
Classifications
-
- 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
- C22B7/006—Wet processes
- C22B7/007—Wet processes by acid leaching
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B15/00—Other processes for the manufacture of iron from iron compounds
-
- 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
- C22B23/00—Obtaining nickel or cobalt
- C22B23/04—Obtaining nickel or cobalt by wet processes
- C22B23/0407—Leaching processes
- C22B23/0415—Leaching processes with acids or salt solutions except ammonium salts solutions
- C22B23/043—Sulfurated acids or salts thereof
-
- 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
- C22B34/00—Obtaining refractory metals
- C22B34/30—Obtaining chromium, molybdenum or tungsten
- C22B34/32—Obtaining chromium
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Treatment Of Sludge (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
The invention provides a method for preparing regenerated iron particles by utilizing metal surface treatment waste, which comprises the following steps: the method comprises the following steps of pretreatment, iron, copper and chromium removal, batching, forming, curing, crushing and magnetic separation, crushing the cured brick by a wet crushing method until the size of the particle is 40-50 mu m, adding water for size mixing until the water content is 50%, then carrying out magnetic separation treatment to obtain regenerated iron particles, and using the tailings after magnetic separation as production raw materials of other products after leaching experiments confirm that the concentrations of heavy metals of nickel and chromium are lower than the standard requirements of hazardous waste. The invention can realize the harmless treatment of the metal surface treatment waste and can fully recycle the iron particles in the metal surface treatment waste for reuse.
Description
Technical Field
The invention relates to the technical field of treatment and comprehensive utilization of metal surface treatment waste, in particular to a method for preparing regenerated iron particles by utilizing the metal surface treatment waste.
Background
In the process of treating and processing metal surfaces in stainless steel enterprises and electroplating enterprises, the stainless steel pickling sludge contains nickel, chromium and iron, and the electroplating sludge contains metal elements such as nickel, copper, zinc, iron and the like, and belongs to hazardous wastes. On the other hand, metal elements such as nickel, chromium, copper, iron and the like in the sludge have higher industrial utilization value, and if the metal elements are not recycled, the metal elements mean huge waste of resources, so that the harmless treatment of the sludge is realized, the valuable metal elements in the sludge are recycled, and the realization of the comprehensive utilization of the sludge resource is not only the requirement of environmental protection, but also the requirement of social sustainable development for realizing circular economy.
Disclosure of Invention
Accordingly, an object of the present invention is to provide a method for producing recycled iron particles from metal surface treatment waste, which can achieve harmless treatment of the metal surface treatment waste and can sufficiently recover and reuse iron particles in the metal surface treatment waste.
To achieve the above objects, the present invention provides a method for preparing regenerated iron particles using metal surface treatment waste, the method comprising:
step 1, pretreatment: carrying out acid leaching treatment on the metal surface treatment waste by using waste acid at normal temperature, carrying out filter pressing on acid leaching liquid subjected to acid leaching treatment to form a first filtrate and a first filter residue, dissolving sulfate formed by metal ions of iron, nickel, chromium and copper in the metal surface treatment waste in the first filtrate, and leaving calcium sulfate and silicon oxide in the first filter residue, wherein the water content of the first filter residue is 60%; wherein the metal surface treatment waste comprises the following components in percentage by mass: 2.5-3.7% of Ni, 2.8-4.1% of Cr, 5.3-7.8% of Fe, 3.8-5.8% of SiO, 18.8-26.5% of Ca, 0.8-1.2% of Cu, 45-62% of water and 4.0-5.9% of the rest; the waste acid comprises the following components in percentage by weight: 3.62-5.4 g/l of Ni, 4.4-6.6 g/l of Cr, 38.9-58.44 g/l of Fe, 0.08-0.12 g/l of Cu, 150-180 g/l of sulfuric acid and 3.68-5.52 g/l of other metals;
step 2, removing iron, copper and chromium: adding a lime solution with the concentration of 15% into the first filtrate, gradually adjusting the pH value of the first filtrate to form an iron hydroxide precipitate, precipitating chromium hydroxide precipitate with copper hydroxide to separate out metal ions of iron, copper and chromium, and performing filter pressing on a product with iron, copper and chromium removed to separate out a second filtrate and a second filter residue with the water content of 60%;
step 3, batching and forming: adding manganese dioxide into the mixture of the first filter residue and the second filter residue, uniformly mixing, and pressing into a square-block-shaped sludge block by a forming machine;
and 4, curing: sending the sludge block into a tunnel kiln for firing, so that metal elements in the sludge block become stable metal oxides, forming covalent structures by iron, chromium and copper metal oxides under the action of high temperature, separating the covalent structures from calcium and silicon, and taking the fired brick out of the kiln after heat preservation and cooling to 80 ℃; and
step 5, crushing and magnetic separation: crushing the solidified brick blocks by a wet crushing method until the particle size is 40-50 mu m, adding water, mixing the slurry until the water content is 50%, and then carrying out magnetic separation treatment to obtain regenerated iron particles, wherein the tailings after the magnetic separation are used as production raw materials of other products after leaching experiments confirm that the concentrations of heavy metals of nickel and chromium are lower than the standard requirement of hazardous waste.
As an optional technical scheme, the magnetic field intensity of the magnetic separation treatment is 2000-3000 gauss.
As an optional technical scheme, in the step 3, after the manganese dioxide is added, the mass ratio of manganese to chromium in the mixture of the first filter residue, the second filter residue and the manganese dioxide is 1: 4-4.5: 15.
as an optional technical scheme, the tunnel kiln body is divided into a preheating zone, a burning zone and a cooling zone, the sludge blocks firstly enter the preheating zone, the temperature is gradually increased from 20 ℃ to 400 ℃ under the heating of waste heat air and hot flue gas of the burning zone, residual moisture is removed at the stage of 20 ℃ to 200 ℃, structural water is removed at the stage of 200 ℃ to 400 ℃, the dried and preheated sludge blocks are sintered in the burning zone, and the temperature is controlled at 1050 ℃ to 1100 ℃; and (3) the bricks after firing enter a cooling zone, and are directly cooled to 80 ℃ by externally-sent cold air and taken out of the kiln.
As an optional technical scheme, the metal surface treatment waste comprises the following components in percentage by mass: 3.1% of Ni, 3.5% of Cr, 6.5% of Fe, 4.8% of SiO, 22.2% of Ca, 1.0% of Cu, 54% of water and 4.9% of the rest; the waste acid comprises the following components in percentage by weight: ni4.52g/l, Cr5.5g/l, Fe 48.7g/l, Cu0.1g/l, sulfuric acid 150g/l, other metals 4.6 g/l.
As an optional technical solution, the pretreatment includes the following steps:
step 11, stirring and size mixing: putting the metal surface treatment waste into a stirrer, synchronously adding water and stirring to prepare mixed slurry, wherein the mass ratio of the metal surface treatment waste to the water is 1: 1.5-1: 2, the water content of the mixed slurry is 75-85%;
step 12, acid leaching: according to the mass ratio of the mixed slurry to the waste acid of 2: 1-1.5: synchronously pumping the mixed slurry and the waste acid into an acid leaching tank, adjusting the pH value of a mixed solution of the mixed slurry and the waste acid to 1-2, and stirring and leaching for 3-5 hours to enable metal ions such as iron, nickel, chromium and copper in the metal surface treatment waste to form sulfate, wherein the concentration of sulfuric acid in the waste acid is 15-18%;
step 13, performing first filter pressing, namely inputting the acid leaching solution formed after the full acid leaching in the step 12 into a plate-and-frame filter press for filter pressing to form a first filtrate and a third filter residue, dissolving sulfate formed by metal ions of iron, nickel, chromium and copper into the first filtrate, and enabling the first filtrate to enter a subsequent filtrate treatment program; and
step 14, water washing and secondary filter pressing: and (3) washing the third filter residue, and performing filter pressing again by using a plate-and-frame filter press to form the first filter residue, wherein the water washing adopts recycled water, and the slag washing water generated by the second filter pressing is recycled to the step 11.
As an optional technical scheme, the mass ratio of the mixed slurry to the waste acid is 2: 1.
as an optional technical solution, the water content of the mixed slurry is 80%.
As an optional technical scheme, the mass ratio of the metal surface treatment waste to water is 1: 2.
as an alternative solution, the metal surface treatment waste and the waste acid are both from the metal surface treatment industry and/or the electroplating industry.
Compared with the prior art, the method utilizes the waste acid in the same industry or similar industry to carry out acid leaching pretreatment on the metal surface treatment waste, and carries out solidification, crushing, magnetic separation and other treatments on the filter residue formed by pretreatment, the magnetically-separated iron particles can be recycled, and the tailings are subjected to leaching experiments to confirm that the concentrations of nickel and chromium heavy metals are lower than the standard requirements of hazardous waste, so that the tailings can be used as production raw materials of other products, not only can the harmless treatment on the waste residue after the metal surface treatment waste is pretreated be realized, but also the iron particles in the waste residue can be fully recovered for recycling, and the method is suitable for industrial production, and has remarkable economic benefit and social benefit.
The advantages and spirit of the present invention will be further understood by the following detailed description of the invention.
Drawings
None.
Detailed Description
The invention provides a method for preparing regenerated iron particles by utilizing metal surface treatment waste, which comprises the following steps:
step 1, pretreatment: carrying out acid leaching treatment on the metal surface treatment waste by using waste acid at normal temperature, carrying out filter pressing on acid leaching liquid subjected to acid leaching treatment to form a first filtrate and a first filter residue, dissolving sulfate formed by metal ions of iron, nickel, chromium and copper in the metal surface treatment waste in the first filtrate, and leaving calcium sulfate and silicon oxide in the first filter residue, wherein the water content of the first filter residue is 60%; wherein the metal surface treatment waste comprises the following components in percentage by mass: 2.5-3.7% of Ni, 2.8-4.1% of Cr, 5.3-7.8% of Fe, 3.8-5.8% of SiO, 18.8-26.5% of Ca, 0.8-1.2% of Cu, 45-62% of water and 4.0-5.9% of the rest; the waste acid comprises the following components in percentage by weight: 3.62-5.4 g/l of Ni, 4.4-6.6 g/l of Cr, 38.9-58.44 g/l of Fe, 0.08-0.12 g/l of Cu, 150-180 g/l of sulfuric acid and 3.68-5.52 g/l of other metals; preferably, the metal surface treatment waste comprises the following components in percentage by mass: 3.1% of Ni, 3.5% of Cr, 6.5% of Fe6, 4.8% of SiO, 22.2% of Ca, 1.0% of Cu, 54% of water and 4.9% of the rest; the waste acid comprises the following components in percentage by weight: ni4.52g/l, Cr5.5g/l, Fe 48.7g/l, Cu0.1g/l, sulfuric acid 150g/l, and other metals 4.6g/l, wherein the metal surface treatment waste and the waste acid come from the metal surface treatment industry and/or the electroplating industry;
step 2, removing iron, copper and chromium: adding a lime solution with the concentration of 15% into the first filtrate, and gradually adjusting the pH value of the first filtrate according to the requirement of the pH value of carbonate precipitates formed by different metal ions, specifically, for example, iron ions form ferric hydroxide precipitates when the pH value is adjusted to 3.5-4, chromium ions form chromium hydroxide precipitates when the pH value is adjusted to 4.5-5, copper ions form copper hydroxide precipitates when the pH value is adjusted to 5-5.5, and calcium sulfate precipitates are formed at the same time, so that metal ions of iron, copper and chromium are separated, and a product for removing iron, copper and chromium is subjected to filter pressing to separate a second filtrate and a second filter residue with the water content of 60%;
step 3, batching and forming: adding manganese dioxide serving as a metal covalent body structure auxiliary agent into a mixture of the first filter residue and the second filter residue, uniformly mixing, and pressing into a square-block-shaped sludge block by a forming machine; after the manganese dioxide is added, the mass ratio of manganese, chromium and iron in the mixture is 1: (4-5): 15; in addition, a small amount of dust is generated during feeding in the batching process, collected and processed by a bag type dust collector to reach the standard and then discharged;
and 4, curing: and (3) feeding the sludge blocks into a tunnel kiln for firing, so that metal elements in the sludge blocks are changed into stable metal oxides, the iron, chromium and copper metal oxides form covalent structures under the action of high temperature, the covalent structures are separated from calcium and silicon, and the fired bricks are taken out of the kiln after being cooled to 80 ℃. Specifically, the tunnel kiln body is divided into a preheating zone, a burning zone and a cooling zone, sludge blocks firstly enter the preheating zone, the temperature is gradually increased from 20-400 ℃ under the heating of waste heat air and hot flue gas of the burning zone, residual moisture is removed at the stage of 20-200 ℃, structural water is removed at the stage of 200-400 ℃, the dried and preheated sludge blocks are sintered in the burning zone, natural gas is used as fuel, a burner is directly inserted into the tunnel kiln, flame is directly combusted in the clearance of the sludge blocks, and the temperature is controlled at 1050-1100 ℃; the bricks after firing enter a cooling zone, and are directly cooled to 80 ℃ by externally-sent cold air and taken out of the kiln; wherein, the fuel combustion waste gas, smoke dust and dry waste gas in the solidification and sintering section are discharged together, and are treated by a bag type dust collector and then discharged after reaching the standard;
step 5, crushing and magnetic separation: cooling the solidified brick, adding water, crushing by a wet crushing method until the particle size is 40-50 mu m, adding water, mixing until the water content is 50%, and then carrying out magnetic separation treatment, wherein the magnetic field intensity of the magnetic separation treatment is 2000-3000 gauss, preferably 2500 gauss, to obtain regenerated iron particles, and drying for later use. The crushing and magnetic separation adopt wet methods, so that dust is not generated basically. The tailings after magnetic separation are used as production raw materials of other products after being confirmed by leaching experiments that the concentrations of heavy metals of nickel and chromium are lower than the standard requirements of hazardous waste, and are specifically reused as concrete brick raw materials.
Further, the pretreatment of the above step 1 includes the steps of:
step 11, stirring and size mixing: putting the metal surface treatment waste into a stirrer, synchronously adding water and stirring to prepare mixed slurry, wherein the mass ratio of the metal surface treatment waste to the water is 1: 1.5-1: 2, the water content of the mixed slurry is 75-85%, preferably, the water content of the mixed slurry is 80%, and the mass ratio of the metal surface treatment waste to the water is 1: 2;
step 12, acid leaching: according to the mass ratio of the mixed slurry to the waste acid of 2: 1-1.5: synchronously pumping the mixed slurry and the waste acid into an acid leaching tank, adjusting the pH value of the mixed solution of the mixed slurry and the waste acid to 1-2, and stirring and leaching for 3-5 hours to enable metal ions such as iron, nickel, chromium and copper in metal surface treatment waste to form sulfate, wherein the concentration of sulfuric acid in the waste acid is 15% -18%, preferably, the concentration of sulfuric acid in the waste acid is 15%, and the mass ratio of the mixed slurry to the waste acid is 2: 1; the metal surface treatment waste and the waste acid are from the metal surface treatment industry and/or the electroplating industry, and the metal surface treatment waste (or sludge) usually contains Ca (OH)2、Fe(OH)2、Cu(OH)2、Ni(OH)2、Cr(OH)3And (3) under the action of sufficient acid liquor with certain concentration, the following common reactions occur:
Ni(OH)2+H2SO4＝NiSO4+2H2O
Cu(OH)2+H2SO4＝CuSO4+2H2O
2Cr(OH)3+3H2SO4＝Cr2(SO4)3+6H2O
2Fe(OH)3+3H2SO4＝Fe2(SO4)3+6H2O
Ca(OH)2+H2SO4＝Ca2SO4+2H2O
in addition, the leaching rate of the metal ions can reach more than 90 percent in the acid leaching process. In addition, acid mist is generated in the acid leaching process, so that the acid leaching equipment adopts closed equipment, and the volatilization of the acid mist can be effectively reduced, so that the acid mist is conveniently collected in a centralized manner and is discharged after reaching the standard after being treated by an acid mist purification tower;
step 13, performing first filter pressing, namely inputting the acid leaching solution formed after the full acid leaching in the step 12 into a plate-and-frame filter press to perform filter pressing to form a first filtrate and a third filter residue, dissolving sulfate formed by metal ions of iron, nickel, chromium and copper into the first filtrate, and enabling the first filtrate to enter a subsequent filtrate treatment procedure, wherein the iron, nickel, copper and chromium can be basically and completely dissolved into the solution, and only a small part of calcium sulfate enters the solution due to small solubility;
step 14, water washing and secondary filter pressing: and (3) washing the third filter residue, and performing filter pressing again by using a plate-and-frame filter press to form the first filter residue, wherein the water washing adopts recycled water, the residue washing water generated by the second filter pressing is recycled to the step (11), and the water content of the first filter residue is 60%.
The metal surface treatment waste and the waste acid are transported by a special hazardous waste transport unit and are temporarily stored in a sludge raw material bin and a waste acid storage tank after entering a factory, and the surface treatment waste and the waste acid can be received after being detected to meet the receiving requirement.
The present invention is further illustrated by the following specific examples.
The reagents and instruments used in the present invention are commercially available products unless otherwise specified.
In the examples 1 to 3, the stainless steel sludge discharged by stainless steel enterprises or electroplating enterprises is used as a treatment sample, and the analysis and detection of the heavy metal components and the content thereof are carried out, wherein the detection results are as follows:
table 1 shows the results of analyzing the contents of components of the treated samples of examples 1 to 3
Example 1
In this embodiment, the method for preparing the regenerated iron particles using the metal surface treatment waste includes the steps of:
step 11, stirring and size mixing: putting the metal surface treatment waste into a stirrer, synchronously adding water and stirring to prepare mixed slurry, wherein the mass ratio of the metal surface treatment waste to the water is 1: 1.5, and the water content of the mixed slurry is 75 percent; in addition, the mass percentages of the components in the metal surface treatment waste and the contents of the components in the waste acid are shown in table 1;
step 12, acid leaching: according to the mass ratio of the mixed slurry to the waste acid of 2: synchronously pumping the mixed slurry and the waste acid into an acid leaching tank, adjusting the pH value of the mixed solution of the mixed slurry and the waste acid to 1-2, and leaching for 3-5 hours under stirring to enable metal ions of iron, nickel, chromium and copper in the metal surface treatment waste to form sulfate, wherein the concentration of sulfuric acid in the waste acid is 15%;
step 13, first pressure filtration: inputting the acid leaching solution formed after the full acid leaching in the step 12 into a plate-and-frame filter press to be subjected to filter pressing to form a first filtrate and a third filter residue, dissolving sulfate formed by metal ions of iron, nickel, chromium and copper into the first filtrate, and enabling the first filtrate to enter a subsequent filtrate treatment procedure, so that a nickel plate and sodium sulfate can be prepared through the subsequent filtrate treatment procedure; and
step 14, water washing and secondary filter pressing: and washing the third filter residue with water, and performing filter pressing again by using a plate-and-frame filter press to form the first filter residue, wherein the water washing adopts reuse water, the residue washing water generated by the second filter pressing is reused in the step 11, and the water content of the first filter residue is 60%.
Step 2, removing iron, copper and chromium: adding a lime solution with the concentration of 15% into the first filtrate, gradually adjusting the pH value of the first filtrate, forming ferric hydroxide precipitate by iron ions when the pH value is 3.5-4, forming chromium hydroxide precipitate by chromium ions when the pH value is 4.5-5, forming copper hydroxide precipitate by copper ions when the pH value is 5-5.5, and simultaneously forming calcium sulfate precipitate, so as to separate out iron, copper and chromium metal ions, and separating out a second filtrate and a second filter residue with the water content of 60% by a product of iron, copper and chromium removal through filter pressing;
step 3, batching and forming: adding manganese dioxide into the mixture of the first filter residue and the second filter residue, so that the mass ratio of manganese, chromium and iron in the mixture is 1: 4: 15, uniformly mixing, and pressing into square-block-shaped sludge blocks by a forming machine;
and 4, curing: sending the sludge blocks into a tunnel kiln for firing, wherein the sludge blocks firstly enter a preheating zone, gradually raising the temperature from 20-400 ℃ under the heating of waste heat air and hot flue gas of the firing zone, removing residual moisture at the stage of 20-200 ℃, removing structural water at the stage of 200-400 ℃, drying and preheating the sludge blocks, sintering the sludge blocks in the firing zone, taking natural gas as fuel, directly inserting a burner into the tunnel kiln, directly burning flame in the clearance of the sludge blocks, and controlling the temperature at 1050-1100 ℃; the bricks after firing enter a cooling zone, and are directly cooled to 80 ℃ by externally-sent cold air and taken out of the kiln;
step 5, crushing and magnetic separation: cooling the solidified bricks, adding water, crushing the bricks by a wet crushing method until the particle size is 40-50 mu m, adding water, mixing the slurry until the water content is 50%, and then carrying out magnetic separation treatment, wherein the magnetic field intensity of the magnetic separation treatment is 2000 gauss to obtain regenerated iron particles, and leaching experiments on tailings after the magnetic separation confirm that the concentration of heavy metals such as nickel and chromium is lower than the standard requirement of hazardous waste;
step 6: chemical analysis: and (3) detecting the component content of the regenerated iron particles and the tailings obtained in the step (5), analyzing the chemical components and the content of the regenerated iron particles and the tailings, and performing a detection method according to 'hazardous waste identification standard leaching toxicity identification' (GB5085.3-2007), wherein the detection results are shown in Table 2.
Example 2
In this embodiment, the method for preparing the regenerated iron particles using the metal surface treatment waste includes the steps of:
step 11, stirring and size mixing: putting the metal surface treatment waste into a stirrer, synchronously adding water and stirring to prepare mixed slurry, wherein the mass ratio of the metal surface treatment waste to the water is 1: 2, the water content of the mixed slurry is 85 percent; in addition, the mass percentages of the components in the metal surface treatment waste and the contents of the components in the waste acid are shown in table 1;
step 12, acid leaching: according to the mass ratio of the mixed slurry to the waste acid of 1.5: synchronously pumping the mixed slurry and the waste acid into an acid leaching tank, adjusting the pH value of the mixed solution of the mixed slurry and the waste acid to 1-2, and leaching for 3-5 hours under stirring to enable metal ions of iron, nickel, chromium and copper in the metal surface treatment waste to form sulfate, wherein the concentration of sulfuric acid in the waste acid is 18%;
step 13, first pressure filtration: inputting the acid leaching solution formed after the full acid leaching in the step 12 into a plate-and-frame filter press to be subjected to filter pressing to form a first filtrate and a third filter residue, dissolving sulfate formed by metal ions of iron, nickel, chromium and copper into the first filtrate, and enabling the first filtrate to enter a subsequent filtrate treatment procedure, so that a nickel plate and sodium sulfate can be prepared through the subsequent filtrate treatment procedure; and
step 14, water washing and secondary filter pressing: and washing the third filter residue with water, and performing filter pressing again by using a plate-and-frame filter press to form the first filter residue, wherein the water washing adopts reuse water, the residue washing water generated by the second filter pressing is reused in the step 11, and the water content of the first filter residue is 60%.
Step 2, removing iron, copper and chromium: adding a lime solution with the concentration of 15% into the first filtrate, gradually adjusting the pH value of the first filtrate, forming ferric hydroxide precipitate by iron ions when the pH value is 3.5-4, forming chromium hydroxide precipitate by chromium ions when the pH value is 4.5-5, forming copper hydroxide precipitate by copper ions when the pH value is 5-5.5, and simultaneously forming calcium sulfate precipitate, so as to separate out iron, copper and chromium metal ions, and separating out a second filtrate and a second filter residue with the water content of 60% by a product of iron, copper and chromium removal through filter pressing;
step 3, batching and forming: adding manganese dioxide into the mixture of the first filter residue and the second filter residue, so that the mass ratio of manganese, chromium and iron in the mixture is 1: 5: 15, uniformly mixing, and pressing into square-block-shaped sludge blocks by a forming machine;
and 4, curing: sending the sludge blocks into a tunnel kiln for firing, wherein the sludge blocks firstly enter a preheating zone, gradually raising the temperature from 20-400 ℃ under the heating of waste heat air and hot flue gas of the firing zone, removing residual moisture at the stage of 20-200 ℃, removing structural water at the stage of 200-400 ℃, drying and preheating the sludge blocks, sintering the sludge blocks in the firing zone, taking natural gas as fuel, directly inserting a burner into the tunnel kiln, directly burning flame in the clearance of the sludge blocks, and controlling the temperature at 1050-1100 ℃; the bricks after firing enter a cooling zone, and are directly cooled to 80 ℃ by externally-sent cold air and taken out of the kiln;
step 5, crushing and magnetic separation: cooling the solidified bricks, adding water, crushing the bricks by a wet crushing method until the particle size is 40-50 mu m, adding water, mixing the slurry until the water content is 50%, and then carrying out magnetic separation treatment, wherein the magnetic field intensity of the magnetic separation treatment is 2500 Gauss, so as to obtain regenerated iron particles, and leaching experiments on tailings after the magnetic separation confirm that the concentration of heavy metals such as nickel and chromium is lower than the standard requirement of hazardous waste;
step 6: chemical analysis: and (3) detecting the component content of the regenerated iron particles and the tailings obtained in the step (5), analyzing the chemical components and the content of the regenerated iron particles and the tailings, and performing a detection method according to 'hazardous waste identification standard leaching toxicity identification' (GB5085.3-2007), wherein the detection results are shown in Table 2.
Example 3
In this embodiment, the method for preparing the regenerated iron particles using the metal surface treatment waste includes the steps of:
step 11, stirring and size mixing: putting the metal surface treatment waste into a stirrer, synchronously adding water and stirring to prepare mixed slurry, wherein the mass ratio of the metal surface treatment waste to the water is 1: 1.8, and the water content of the mixed slurry is 80%; in addition, the mass percentages of the components in the metal surface treatment waste and the contents of the components in the waste acid are shown in table 1;
step 12, acid leaching: according to the mass ratio of the mixed slurry to the waste acid of 1.8: synchronously pumping the mixed slurry and the waste acid into an acid leaching tank, adjusting the pH value of the mixed solution of the mixed slurry and the waste acid to 1-2, and leaching for 3-5 hours under stirring to enable metal ions of iron, nickel, chromium and copper in the metal surface treatment waste to form sulfate, wherein the concentration of sulfuric acid in the waste acid is 16%;
step 13, first pressure filtration: inputting the acid leaching solution formed after the full acid leaching in the step 12 into a plate-and-frame filter press to be subjected to filter pressing to form a first filtrate and a third filter residue, dissolving sulfate formed by metal ions of iron, nickel, chromium and copper into the first filtrate, and enabling the first filtrate to enter a subsequent filtrate treatment procedure, so that a nickel plate and sodium sulfate can be prepared through the subsequent filtrate treatment procedure; and
step 14, water washing and secondary filter pressing: and washing the third filter residue with water, and performing filter pressing again by using a plate-and-frame filter press to form the first filter residue, wherein the water washing adopts reuse water, the residue washing water generated by the second filter pressing is reused in the step 11, and the water content of the first filter residue is 60%.
Step 2, removing iron, copper and chromium: adding a lime solution with the concentration of 15% into the first filtrate, gradually adjusting the pH value of the first filtrate, forming ferric hydroxide precipitate by iron ions when the pH value is 3.5-4, forming chromium hydroxide precipitate by chromium ions when the pH value is 4.5-5, forming copper hydroxide precipitate by copper ions when the pH value is 5-5.5, and simultaneously forming calcium sulfate precipitate, so as to separate out iron, copper and chromium metal ions, and separating out a second filtrate and a second filter residue with the water content of 60% by a product of iron, copper and chromium removal through filter pressing;
step 3, batching and forming: adding manganese dioxide into the mixture of the first filter residue and the second filter residue, so that the mass ratio of manganese, chromium and iron in the mixture is 1: 4.5: 15, uniformly mixing, and pressing into square-block-shaped sludge blocks by a forming machine;
and 4, curing: sending the sludge blocks into a tunnel kiln for firing, wherein the sludge blocks firstly enter a preheating zone, gradually raising the temperature from 20-400 ℃ under the heating of waste heat air and hot flue gas of the firing zone, removing residual moisture at the stage of 20-200 ℃, removing structural water at the stage of 200-400 ℃, drying and preheating the sludge blocks, sintering the sludge blocks in the firing zone, taking natural gas as fuel, directly inserting a burner into the tunnel kiln, directly burning flame in the clearance of the sludge blocks, and controlling the temperature at 1050-1100 ℃; the bricks after firing enter a cooling zone, and are directly cooled to 80 ℃ by externally-sent cold air and taken out of the kiln;
step 5, crushing and magnetic separation: cooling the solidified brick, adding water, crushing by a wet crushing method until the particle size is 40-50 mu m, adding water, mixing until the water content is 50%, performing magnetic separation treatment, wherein the magnetic field strength of the magnetic separation treatment is 3000 Gauss to obtain regenerated iron particles, and determining that the concentration of heavy metals such as nickel and chromium in tailings after the magnetic separation is lower than the standard requirement of hazardous waste through a leaching experiment;
step 6: chemical analysis: and (3) detecting the component content of the regenerated iron particles and the tailings obtained in the step (5), analyzing the chemical components and the content of the regenerated iron particles and the tailings, and performing a detection method according to 'hazardous waste identification standard leaching toxicity identification' (GB5085.3-2007), wherein the detection results are shown in Table 2.
TABLE 2 results of chemical analyses of the regenerated iron particles and tailings
The contents in tables 1 and 2 show that the metal surface treatment waste can be used for preparing regenerated iron particles for recycling of the iron particles, and the leaching concentrations of nickel and chromium in tailings are less than the hazardous waste identification standard leaching toxicity identification (GB 5085.3-2007).
In conclusion, the method utilizes the waste acid in the same industry or similar industry to carry out acid leaching pretreatment on the metal surface treatment waste, and carries out solidification, crushing, magnetic separation and other treatments on the filter residue formed by pretreatment, the magnetically-separated iron particles can be recycled, and the tailings are subjected to leaching experiments to confirm that the concentrations of the heavy metals of nickel and chromium are lower than the standard requirements of hazardous wastes, so that the tailings can be used as production raw materials of other products, not only can the harmless treatment on the waste residue after the metal surface treatment waste is pretreated be realized, but also the iron particles in the waste residue can be fully recovered for recycling, and the method is suitable for industrial production and has remarkable economic and social benefits.
The above detailed description of the preferred embodiments is intended to more clearly illustrate the features and spirit of the present invention, and is not intended to limit the scope of the present invention by the preferred embodiments disclosed above. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims. The scope of the claims to be accorded the invention is therefore to be accorded the broadest interpretation so as to encompass all such modifications and equivalent arrangements as is known in the art.
Claims (10)
1. A method for preparing regenerated iron particles using metal surface treatment waste, comprising:
step 1, pretreatment: carrying out acid leaching treatment on the metal surface treatment waste by using waste acid at normal temperature, carrying out filter pressing on acid leaching liquid subjected to acid leaching treatment to form a first filtrate and a first filter residue, dissolving sulfate formed by metal ions of iron, nickel, chromium and copper in the metal surface treatment waste in the first filtrate, and leaving calcium sulfate and silicon oxide in the first filter residue, wherein the water content of the first filter residue is 60%; wherein the metal surface treatment waste comprises the following components in percentage by mass: 2.5-3.7% of Ni, 2.8-4.1% of Cr, 5.3-7.8% of Fe, 3.8-5.8% of SiO, 18.8-26.5% of Ca, 0.8-1.2% of Cu, 45-62% of water and 4.0-5.9% of the rest; the waste acid comprises the following components in percentage by weight: 3.62-5.4 g/l of Ni, 4.4-6.6 g/l of Cr, 38.9-58.44 g/l of FeC, 0.08-0.12 g/l of Cu, 150-180 g/l of sulfuric acid and 3.68-5.52 g/l of other metals;
step 2, removing iron, copper and chromium: adding a lime solution with the concentration of 15% into the first filtrate, gradually adjusting the pH value of the first filtrate to form an iron hydroxide precipitate, a chromium hydroxide precipitate and a copper hydroxide precipitate so as to separate out metal ions of iron, copper and chromium, and performing filter pressing on a product with iron, copper and chromium removed to separate out a second filtrate and a second filter residue with the water content of 60%;
step 3, batching and forming: adding manganese dioxide into the mixture of the first filter residue and the second filter residue, uniformly mixing, and pressing into a square-block-shaped sludge block by a forming machine;
and 4, curing: sending the sludge block into a tunnel kiln for firing, so that metal elements in the sludge block become stable metal oxides, forming covalent structures by iron, chromium and copper metal oxides under the action of high temperature, separating the covalent structures from calcium and silicon, and taking the fired brick out of the kiln after heat preservation and cooling to 80 ℃; and
step 5, crushing and magnetic separation: crushing the solidified brick blocks by a wet crushing method until the particle size is 40-50 mu m, adding water, mixing the slurry until the water content is 50%, and then carrying out magnetic separation treatment to obtain regenerated iron particles, wherein the tailings after the magnetic separation are used as production raw materials of other products after leaching experiments confirm that the concentrations of heavy metals of nickel and chromium are lower than the standard requirement of hazardous waste.
2. The method for preparing recycled iron particles using metal surface treatment waste as set forth in claim 1, wherein the magnetic field intensity of the magnetic separation treatment is 2000 to 3000 gauss.
3. The method for preparing recycled iron particles from metal surface treatment waste according to claim 1, wherein in the step 3, after the manganese dioxide is added, the mass ratio of the manganese to the chromium in the mixture of the first filter residue, the second filter residue and the manganese dioxide is 1: 4-4.5: 15.
4. the method of claim 1, wherein the tunnel kiln body is divided into a preheating zone, a burning zone and a cooling zone, the sludge blocks firstly enter the preheating zone, the temperature is gradually raised from 20 to 400 ℃ under the heating of the residual air and the hot flue gas of the burning zone, wherein the residual moisture is removed at the stage of 20 to 200 ℃, the structural water is removed at the stage of 200 to 400 ℃, the dried and preheated sludge blocks are sintered in the burning zone, and the temperature is controlled at 1050 to 1100 ℃; and (3) the bricks after firing enter a cooling zone, and are directly cooled to 80 ℃ by externally-sent cold air and taken out of the kiln.
5. The method for preparing recycled iron particles using metal surface treatment waste as claimed in claim 1, wherein the metal surface treatment waste comprises the following components in percentage by mass: 3.1 percent of Ni, 3.5 percent of Cr, 6.5 percent of Fe, 4.8 percent of SiO, 22.2 percent of Ca, 1.0 percent of Cu, 54 percent of water and 4.9 percent of the rest; the waste acid comprises the following components in percentage by weight: ni4.52g/l, Cr5.5g/l, Fe 48.7g/l, Cu0.1g/l, sulfuric acid 150g/l, other metals 4.6 g/l.
6. The method for preparing regenerated iron particles using metal surface treatment waste as set forth in claim 1, wherein the pretreatment comprises the steps of:
step 11, stirring and size mixing: putting the metal surface treatment waste into a stirrer, synchronously adding water and stirring to prepare mixed slurry, wherein the mass ratio of the metal surface treatment waste to the water is 1: 1.5-1: 2, the water content of the mixed slurry is 75-85%;
step 12, acid leaching: according to the mass ratio of the mixed slurry to the waste acid of 2: 1-1.5: synchronously pumping the mixed slurry and the waste acid into an acid leaching tank, adjusting the pH value of a mixed solution of the mixed slurry and the waste acid to 1-2, and stirring and leaching for 3-5 hours to enable metal ions such as iron, nickel, chromium and copper in the metal surface treatment waste to form sulfate, wherein the concentration of sulfuric acid in the waste acid is 15-18%;
step 13, performing first filter pressing, namely inputting the acid leaching solution formed after the full acid leaching in the step 12 into a plate-and-frame filter press for filter pressing to form a first filtrate and a third filter residue, dissolving sulfate formed by metal ions of iron, nickel, chromium and copper into the first filtrate, and enabling the first filtrate to enter a subsequent filtrate treatment program; and
step 14, water washing and secondary filter pressing: and (3) washing the third filter residue, and performing filter pressing again by using a plate-and-frame filter press to form the first filter residue, wherein the water washing adopts recycled water, and the slag washing water generated by the second filter pressing is recycled to the step 11.
7. The method for preparing recycled iron particles using metal surface treatment waste according to claim 6, wherein the mass ratio of the mixed slurry to the waste acid is 2: 1.
8. the method for preparing recycled iron particles using metal surface treatment waste as claimed in claim 6, wherein the mixed slurry has a water content of 80%.
9. The method for preparing regenerated iron particles using metal surface treatment waste as set forth in claim 6, wherein the mass ratio of the metal surface treatment waste to water is 1: 2.
10. the method for preparing recycled iron granules from metal surface treatment waste according to claim 1, wherein the metal surface treatment waste and the waste acid are both from the metal surface treatment industry.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811314336.XA CN109321752B (en) | 2018-11-06 | 2018-11-06 | Method for preparing regenerated iron particles by using metal surface treatment waste |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811314336.XA CN109321752B (en) | 2018-11-06 | 2018-11-06 | Method for preparing regenerated iron particles by using metal surface treatment waste |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109321752A CN109321752A (en) | 2019-02-12 |
| CN109321752B true CN109321752B (en) | 2020-06-12 |
Family
ID=65259407
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811314336.XA Active CN109321752B (en) | 2018-11-06 | 2018-11-06 | Method for preparing regenerated iron particles by using metal surface treatment waste |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109321752B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109400035B (en) * | 2018-11-06 | 2021-08-13 | 泰州华昊废金属综合利用有限公司 | Method for preparing concrete brick by utilizing metal surface treatment waste |
| CN110605105A (en) * | 2019-08-23 | 2019-12-24 | 北京航天国环技术有限公司 | Method for regenerating metal from waste activated carbon |
| CN113772739B (en) * | 2021-09-14 | 2024-04-12 | 周丹丹 | Clean production method for recycling iron-chromium powder from stainless steel pickling wastewater and waste liquid |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54119331A (en) * | 1978-03-09 | 1979-09-17 | Agency Of Ind Science & Technol | Separating method of zinc and/or iron |
| CN102786192A (en) * | 2012-07-29 | 2012-11-21 | 横峰县远盛金属资源回收利用有限公司 | Electroplating sludge resource recovery process |
| CN103343229A (en) * | 2013-06-28 | 2013-10-09 | 江西理工大学 | Method for comprehensively recovering valuable metals from electroplating waste mud |
| CN107338364A (en) * | 2017-06-15 | 2017-11-10 | 江苏省冶金设计院有限公司 | A kind of method for preparing ferromanganese pearl |
| CN107417148A (en) * | 2017-09-04 | 2017-12-01 | 青川县天运金属开发有限公司 | In a kind of electroplating sludge after METAL EXTRACTION tailings processing method |
-
2018
- 2018-11-06 CN CN201811314336.XA patent/CN109321752B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54119331A (en) * | 1978-03-09 | 1979-09-17 | Agency Of Ind Science & Technol | Separating method of zinc and/or iron |
| CN102786192A (en) * | 2012-07-29 | 2012-11-21 | 横峰县远盛金属资源回收利用有限公司 | Electroplating sludge resource recovery process |
| CN103343229A (en) * | 2013-06-28 | 2013-10-09 | 江西理工大学 | Method for comprehensively recovering valuable metals from electroplating waste mud |
| CN107338364A (en) * | 2017-06-15 | 2017-11-10 | 江苏省冶金设计院有限公司 | A kind of method for preparing ferromanganese pearl |
| CN107417148A (en) * | 2017-09-04 | 2017-12-01 | 青川县天运金属开发有限公司 | In a kind of electroplating sludge after METAL EXTRACTION tailings processing method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109321752A (en) | 2019-02-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109127654B (en) | Low-pollution secondary aluminum ash treatment method | |
| CN101643243B (en) | Method for recycling copper, nickel, chromium, zinc and iron from plating sludge | |
| CN109321752B (en) | Method for preparing regenerated iron particles by using metal surface treatment waste | |
| CN109487078B (en) | Resource utilization method for cooperative treatment of high-iron red mud and waste cathode | |
| CN109621276A (en) | A kind of method that richness iron copper ashes handles arsenic in nonferrous smelting waste acid | |
| CN101618929A (en) | Method of treating alkaline sludge containing heavy metal as resources | |
| CN101407355B (en) | Method for comprehensively utilizing iron vitriol dreg of yellow sodium | |
| CN112830699B (en) | Cement admixture, preparation method and application | |
| CN101905950A (en) | Novel chromium slag innocent treatment method | |
| CN103232068A (en) | Recycling and reutilization process for treating chromium slag and wastewater | |
| CN108249892A (en) | A kind of method that cyanidation tailings harmless treatment prepares fired brick | |
| CN112725629A (en) | Preparation method for extracting nonferrous metal and reduced iron from steel slag | |
| CN107287451A (en) | A kind of chromaking oxidizing roasting acid-leaching vanadium-extracted method of vanadium slag | |
| Shi et al. | Status of research on the resource utilization of stainless steel pickling sludge in China: a review | |
| WO2023004925A1 (en) | Method for enriching and recovering chromium resources by synergistic utilization of chromium-containing sludge and chromium-containing waste residue | |
| CN114164346A (en) | Method for synergistically recovering valuable metals in chromium-containing waste residues and carbon-containing waste materials | |
| CN101450843B (en) | Iron and aluminum complex ore comprehensive utilization method | |
| CN209968029U (en) | Waste gas treatment system for recycling metal surface treatment waste | |
| CN109207736B (en) | Method for producing ferrochromium alloy and aluminum oxide by using chromium-containing aluminum mud and red mud | |
| CN109517996B (en) | Process for extracting iron in sulfuric acid cinder by aid of enhanced acid leaching method | |
| CN109400035B (en) | Method for preparing concrete brick by utilizing metal surface treatment waste | |
| CN109536711B (en) | Recycling treatment system for metal surface treatment waste | |
| CN114558440B (en) | High-efficiency zinc extraction coupling pulp flue gas desulfurization carbon fixation process by high-chlorine zinc gray ammonia-ammonium sulfate method | |
| CN104711428A (en) | Method for preparing and recovering noble metal in pickling sludge | |
| CN101100709B (en) | Method for reclaiming chromium in vanadium oxides producing process |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |