Leaded zinc waste residue of a kind of usefulness or lead-zinc are produced the method for metallic lead and zinc
Technical field
Leaded zinc waste residue of a kind of usefulness or lead-zinc are produced the method for metallic lead and zinc, relate to the method that the leaded zinc waste residue of a kind of usefulness is produced metallic lead and zinc, belong to non-ferrous metal and reclaim and the reclamation of solid wastes field.
Technical background
Plumbous zinc is of many uses, and lead is mainly used in fields such as lead acid cell, cable sheath, machinofacture, and metal zinc is mainly used in fields such as drying battery manufacturing, coating, metallurgy.At present, plumbous raw materials for production are leadedly to adopt sintering-air blast tradition refining splicer skill basically greater than 50% lead glance, and this technology produces a large amount of SO in process of production
2And lead dust, environmental pollution is serious.The raw materials for production of zinc are to contain zinc greater than 40% zink sulphide, adopt mainly that roasting-acidleach-removal of impurities-sour electrolytic acid system is produced zinc technology, but the SO that in this technological process, exists roasting to produce equally
2Pollution problem, simultaneously since in leaching process most metal ion all can enter acid solution, cause the removal of impurities flow process complicated and need to consume a large amount of zinc powders, also there are shortcomings such as energy consumption height in electrolytic process.In addition, adopt the pyrometallurgical smelting technology of blast furnace zinc metallurgy owing to can produce lead and zinc simultaneously, and cost is lower, has also obtained certain application in developing country, but this technology will be carried out sintering equally, and sintering returning charge rate is higher, the SO that produces in the process
2Also relatively more serious with the pollution of dust.Oxygen bottom-blowing-blast furnace reduction refining splicer skill is able to successful Application in recent years, but owing to limited by resources supplIes, present domestic plumbous zinc output does not satisfy the market requirement, and for remedying domestic insufficient raw material, country needs cost a large amount of foreign exchange imported raw material and goods.Therefore, obtained paying close attention to widely to the development and use of plumbous zinc oxidized ore and to the comprehensive reutilization and the resource utilization of leaded zinc waste residue.
Domestic lead-zinc produces aboundresources and is widely distributed, in Yunnan, all there are bigger reserves on ground such as Guizhou, Sichuan, Xinjiang.But oxidized ore physicochemical property complexity, plumbous zinc sorts the enrichment difficulty, and metal recovery rate is lower, and the ore average grade is lower, and the method for therefore traditional plumbous zinc of pyrometallurgical smelting is restricted.
In addition, in each commercial run, produce a large amount of leaded zinc refuses, in the zinc sulfide white production process, the zinc sulfide white of production unit weight discharging scrap lead zinc mud 0.15-0.35t, wherein lead content is generally 20%-40%, and zinc content is 7%-15%.Except that containing a certain amount of iron, also can contain a large amount of metals such as plumbous zinc in the flue dust that Steel Plant produce.The copper smelting process, the leaching process of zinc oxide ore, plumbous pyrometallurgical smelting process also all can produce a large amount of plumbous zinc refuses.These plumbous zinc refuses are because the content of heavy metals such as plumbous zinc is higher, therefore belong to Hazardous wastes, but simultaneously these refuses also are the secondary raw materials of the important plumbous zinc of renewable product, therefore how it are carried out safe treatment and disposal and comprehensive utilization also becomes a urgent problem.The most frequently used waste treatment method is to adopt pyrogenic process to reclaim metal at present, promptly metals such as plumbous zinc is evaporated the method for gathering dust and reclaiming under hot conditions.This method energy consumption height, product purity is low, and the lead dust environmental pollution that produces in the process is serious.The another kind of method that reclaims plumbous zinc is the method for hydrometallurgic recovery, Chinese patent CN1450182A has announced a kind of method with zinc oxide ore production high purity zinc powder, promptly leach with highly basic, with sulfide as the lead in the separating agent precipitate and separate leach liquor, filter, lead content is higher in the filter residue, can sell the highly purified metallic zinc of the direct electrolysis production of the scavenging solution after the filtration.
Summary of the invention
The objective of the invention is to disclose a kind of technology is simple, energy consumption is lower, with low cost leaded zinc waste residue of usefulness or low-grade lead-zinc method as raw material production lead and zinc.
In order to achieve the above object, it is raw material that the present invention adopts the waste residue of leaded zinc or low-grade lead-zinc, leaches with highly basic, and plumbous, zinc enters solution, filters then, and the direct electrolysis of filtrate obtains lead bullion, and the electrolytic solution behind electrolytic lead electrolysis again gets metal zinc.Concrete steps are as follows: lead-zinc residue or lead-zinc are crushed to 0.1-1mm, it then is the strong base solution leaching of 1-10M with concentration, its consumption proportion is that 1 ton of raw material needs 1-7 cubic meter strong base solution, and extraction temperature is 10-100 ℃, agitation leach 30-1000 minute.Filter then, filter residue discharges after washing, and filtrate is solution leaded, zinc.Because equilibrium potential plumbous, zinc differs bigger, therefore can directly adopt electrolytic method optionally to distinguish electrolysis production lead and zinc.The plumbous process of electrolysis production adopts stainless steel as the cathode and anode material, at 20-70 ℃, and 100-1000A/m
2Constant-current electrolysis 1-5h under the current density condition, bath voltage keeps stable earlier in the electrolytic process, carry out along with electrolytic, bath voltage rises, its value is subjected to the influence of free alkali concentration, temperature, pole span, current density, feedstock property etc., when bath voltage rises to 1.8-2.5V, stops electrolysis, be the lead bullion of the leaded 97-99.9% of output on the negative electrode, but electrorefining is produced electricity lead No. one after densification.Whole plumbous electrolytic process current efficiency is 85-95%, and energy consumption is 0.4-0.7kwh/kg.The remaining zinc electrolyte that contains is used for electrolysis production zinc again, adopts stainless steel to make anode, and titanium alloy is made negative electrode, at 30-50 ℃, and 2.5-3.5V, 500-1500A/m
2Electrolysis 1-10h under the current density condition, last, the zinc powder of output is dried under the protection of rare gas element on the negative electrode, finally obtains the one-level metal zinc, and full zinc content reaches 98-99.21% in the zinc powder, and metallic zinc is 96-97.87%.After electrolysis finished, remaining electrolytic solution directly was circulated in next alkali leaching flow process.
The present invention has following advantage:
1. the present invention leaches with highly basic, and the metal in the raw material has only aluminium, lead, zinc and a spot of copper, chromium can enter solution, so the removal of impurities process is simple.
2. when the present invention is with lead in the electrochemical principle separation leach liquor and zinc, at first select the lead in the electrolytic solution, the electrolytic lead process can be removed a spot of other metallic impurity in the solution simultaneously, the output lead bullion, and this process current efficiency height, energy consumption is lower.The electrolytic zinc process is compared with the acid system process, and energy consumption is also lower.Therefore, the present invention has favorable economic benefit.
3. the refuse of leaded zinc filters through leaching, and filter residue is after water washing, and toxicity leaching experiment result is a nontoxicity, can be used as Ordinary solid waste and handles, and has environmental benefit preferably.
Description of drawings
Fig. 1 is a process flow sheet of the present invention
Embodiment
Embodiment 1
See also Fig. 1.With the plumbous zinc gray of certain factory (leaded zinc waste residue) is raw material, and its composition is as shown in table 1:
The plumbous zinc gray composition of certain factory of table 1
Composition |
Zn |
Pb |
Cu |
Fe |
Al |
Ca |
As |
Sb |
Content (%) |
37.53 |
13.69 |
2.33 |
1.13 |
0.76 |
1.31 |
0.026 |
0.017 |
With the above-mentioned plumbous zinc gray of 500g, immerse the NaOH solution of 5L5mol/L earlier, extraction temperature is 30 ℃, stirs 200 minutes under 500 rev/mins rotating speed, and the plumbous zinc in the plumbous zinc gray enters solution.Filtered while hot obtains filter residue and filtrate then.Filtrate component is as shown in table 2:
The plumbous zinc gray alkali leaching liquor of table 2 is formed
Composition |
Zn q |
Pb |
Cu |
Fe |
Al |
Ca |
As |
Sb |
Concentration (g/L) |
35.23 |
12.87 |
0.005 |
0.05 |
0.59 |
0.17 |
0.02 |
0.01 |
After filter residue was used NaOH solution and water washing, washing water returned as highly basic leaching circulation, washed-residue landfill.Filtrate directly is used for electrolytic lead, adopts stainless material as negative electrode and anode, and at 20-30 ℃, current density is 400A/m
2, voltage is 2.0-2.5V, and electrolysis 4h obtains purity and is 97% lead bullion on negative electrode, and electrolytic process current efficiency is 88%, and energy consumption is a 0.7kwh/kg lead.Zinciferous electrolytic solution behind the electrolytic lead is at 30-40 ℃, 2.7-3.5V, 1000-1500A/m
2Condition under electrolytic zinc, 5h (make anode with stainless steel, titanium alloy is made negative electrode), last, on negative electrode, obtain metal zinc, full zinc content is 99.21% in the zinc powder, metallic zinc is 97.87%, process in zinc electrolyzing current efficiency is 85%, energy consumption is a 2.5kwh/kg zinc.After electrolysis finished, electrolytic solution directly was circulated in next alkali leaching flow process.
Embodiment 2
With the lead-zinc is raw material, and its composition is as shown in table 3:
Certain lead-zinc composition of table 3
Composition |
Zn |
Pb |
Cu |
Si |
Al |
Ca |
As |
Sb |
Content (%) |
14.30 |
51.61 |
0.88 |
0.25 |
0.46 |
2.21 |
0.33 |
2.06 |
The above-mentioned lead-zinc of 240g is crushed to 0.1-1mm, immerses the NaOH solution of 6L5mol/L then, extraction temperature is 90 ℃, stirs 100 minutes under 1000 rev/mins rotating speed, and the plumbous zinc in the breeze enters solution.Filtered while hot then, filtrate component is as shown in table 4:
Table 4 lead-zinc alkali leaching liquor is formed
Composition |
Zn |
Pb |
Cu |
Si |
Al |
Ca |
As |
Sb |
Concentration (g/L) |
4.77 |
19.84 |
0.20 |
0.06 |
0.18 |
0.4 |
0.10 |
0.13 |
Landfill after filter residue usefulness NaOH solution and the water washing.Filtrate directly is used for electrolytic lead, adopts stainless material as cathode and anode, and at 30-50 ℃, current density is 1000A/m
2, voltage is 1.8-2.0V, electrolysis 2h obtains purity and is 98.5% lead bullion on negative electrode.Contain zinc electrolyte at 40-50 ℃, 2.5-3.0V, 500-1000A/m behind the electrolytic lead
2Condition under electrolytic zinc, 2h, last, on negative electrode, obtain the one-level metal zinc.Full zinc content reaches 98% in the zinc powder, and metallic zinc is 96%.After electrolysis finished, residue electrolytic solution directly was circulated in next alkali leaching flow process.