CN104926036A - Cyanogen-containing tailing slag treatment method - Google Patents
Cyanogen-containing tailing slag treatment method Download PDFInfo
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- CN104926036A CN104926036A CN201510320845.3A CN201510320845A CN104926036A CN 104926036 A CN104926036 A CN 104926036A CN 201510320845 A CN201510320845 A CN 201510320845A CN 104926036 A CN104926036 A CN 104926036A
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Abstract
The invention discloses a cyanogen-containing tailing slag treatment method. The method comprises five steps of slurry mixing, ozone oxidation, chemical catalytic oxidation, solid-liquid separation and deep up-to-standard treatment. During treatment of cyanogen-containing tailing slag, firstly, pollutants in ore slurry are removed with an ozone oxidation method and a chemical catalytic oxidation method, then, solid-liquid separation is performed, harmless stockpiling of the tailing slag is performed, and a slurry fluid is continuously subjected to slurry mixing of the tailing slag or further up-to-standard treatment for discharge. Due to the characteristics of complexity of the pollutants contained in cyanogen-containing tailing slag of a gold mine and difficulty in treatment, mixed slurry is subjected to solid-liquid separation after oxidation treatment, solids and liquids are treated respectively, accordingly, harmless treatment of the tailing slag and cyclic utilization or up-to-standard discharge of the mixed slurry fluid are realized, and the method has the advantages of good treatment effect, high treatment efficiency, stable system operation, simple and practical technological process, convenience in industrial application and the like.
Description
Technical field
The present invention relates to field of Environment Protection Pollutant Treatment method, particularly a kind of cyanogen-containing tailing slag administering method.
Background technology
Because the most of gold mine of China adopts Cyanide Process always, in golden production process, produce a large amount of cyanogen waste residue that contains is deposited in Tailings Dam, along with the expansion of golden production scale and the prolongation of production history, accumulating amount containing cyanogen waste residue is increasing year by year, take a large amount of soil, these waste residues are due to containing prussiate and heavy metal, become the ubiquitous Hazardous wastes of gold mine enterprise, at Tailings Dam Anti-seeping technology improper or maintenance management not in time time, will ooze because drenching with rain down to produce surrounding enviroment and underground water containing prussiate in cyanogen waste residue and pollute.Along with the appearance of new environmental law is implemented, the gold mine enterprise of domestic cyanidation technology is in the urgent need to realizing repair process to the cyanogen waste residue that contains of Tailings Dam, reduce the content of prussiate and heavy metal in waste residue, make Hazardous wastes become general solid waste, thus realize the recycling of waste residue further.From current domestic gold industry containing cyanogen Solid state fermentation situation, still do not have advanced and mature containing cyanogen controlling waste residue method.
Summary of the invention
Object of the present invention is exactly the problems referred to above existed for existing treatment process, and provides the cyanogen-containing tailing slag administering method that a kind of technical process is simple, treatment effect good, processing efficiency is high, stable.
The present invention is according to the feature containing multiple pollutants such as prussiate, thiocyanate-and heavy metals in gold mine cyanogen-containing tailing slag, add water after sizing mixing, first select Ozonation and chemical catalytic oxidation method by the pollutant removal in ore pulp, then solid-liquid separation is carried out, mine tailings are innoxious to be stored up, and slurries proceed sizing mixing of mine tailings or further process discharge up to standard.
The present invention includes following steps:
(1), size mixing: get mine tailings and add water and to size mixing under whipped state process, size mixing time at least 10min;
(2), ozone Oxidation Treatment: the ore pulp evenly of sizing mixing is placed in ozone oxidation groove, and pass into ozone and carry out oxide treatment from the micro-hole aerator of reactor bottom, the treatment time is 30min at least;
(3), pH regulator: the ore pulp after ozone Oxidation Treatment adds acid medicine and regulates between slurry pH to 7 ~ 9, if the slurry pH after ozone Oxidation Treatment is between 7 ~ 9, can regulate;
(4), hydrogen peroxide oxidation process: regulated the ore pulp of pH value to add hydrogen peroxide reagent under whipped state and carried out oxide treatment, or added hydrogen peroxide reagent and copper sulfate reagent and carry out catalytic oxidation treatment;
(5), solid-liquid separation: the ore pulp after hydrogen peroxide oxidation process carries out solid-liquid separation by the solid-liquid separation method of thickener, settling tank, filter, whizzer, slag after separation enters slag field and stores up or prepare architecture engineering material, slurries after separation turn back to the process of sizing mixing of next round mine tailings, or are further processed;
(6), cyanogen process falls in slurries biology: the slurries after solid-liquid separation enter biology and fall cyanogen treatment reactor, and cyanogen flora and nutritive substance fall in access biology, and pass into air by micro-hole aerator and carry out biology and fall cyanogen process, the treatment time is at least 2h.
(7), biological filter process: the slurries after cyanogen process falls in biology enter biological filter chamber treatment system, and the treatment time is at least 1h.
(8), qualified discharge: the slurries qualified discharge after the process of biological filter.
In described step (1), the mass ratio of sizing mixing of mine tailings and water is 1:1 ~ 1:10.
In described step (2), the material of micro-hole aerator is stainless steel, pottery or titanium alloy, and the intake of ozone is 2 ~ 8 times of the pollutent quality sum of prussiate and COD in ore pulp.
In described step (3), acid medicine is sulfuric acid, hydrochloric acid, ferrous sulfate or ferric sulfate.
In described step (4), the add-on of hydrogen peroxide reagent is 0.5 ~ 5 times of the pollutent quality sum of prussiate and COD in ore pulp.
In described step (6), fall cyanogen flora be in streptococcus, Staphylococcus, bacillus, brevibacterium sp, pseudomonas one or more bacterial strains composition, nutritive substance is for falling part carbon nitrogen source needed for cyanogen flora and inorganic salt, slurry temperature remains on 20 ~ 35 DEG C, and the material of micro-hole aerator is stainless steel, pottery or titanium alloy.
In described step (7), biological filter chamber treatment system is in series by one or more levels biological filter, water-distributing device and micro-hole aerator is provided with at the bottom of pond, biological filter, it is the active carbon filler layer of biofilm above micro-hole aerator, biofilm bacterial classification is nitrite bacteria and nitrobacteria, and during operation, vapour-liquid ratio is 1 ~ 5:1.
Beneficial effect of the present invention:
The present invention is according to, unmanageable feature complicated containing pollutent in gold mine cyanogen-containing tailing slag, the mode that solid-liquid separation processes respectively is carried out after adopting oxide treatment of sizing mixing, realize the harmless treatment of mine tailings and adjusting slurry recycle or qualified discharge, have that treatment effect is good, processing efficiency is high, system run all right, technical process are simple and practical, be convenient to realize the advantages such as industrial application, have broad application prospects.
Embodiment
The present invention includes following steps:
(1), size mixing: get mine tailings and add water and to size mixing under whipped state process, size mixing time at least 10min;
(2), ozone Oxidation Treatment: the ore pulp evenly of sizing mixing is placed in ozone oxidation groove, and pass into ozone and carry out oxide treatment from the micro-hole aerator of reactor bottom, the treatment time is 30min at least;
(3), pH regulator: the ore pulp after ozone Oxidation Treatment adds acid medicine and regulates between slurry pH to 7 ~ 9, if the slurry pH after ozone Oxidation Treatment is between 7 ~ 9, can regulate;
(4), hydrogen peroxide oxidation process: regulated the ore pulp of pH value to add hydrogen peroxide reagent under whipped state and carried out oxide treatment, or added hydrogen peroxide reagent and copper sulfate reagent and carry out catalytic oxidation treatment;
(5), solid-liquid separation: the ore pulp after hydrogen peroxide oxidation process carries out solid-liquid separation by the solid-liquid separation method of thickener, settling tank, filter, whizzer, slag after separation enters slag field and stores up or prepare architecture engineering material, slurries after separation turn back to the process of sizing mixing of next round mine tailings, or are further processed;
(6), cyanogen process falls in slurries biology: the slurries after solid-liquid separation enter biology and fall cyanogen treatment reactor, and cyanogen flora and nutritive substance fall in access biology, and pass into air by micro-hole aerator and carry out biology and fall cyanogen process, the treatment time is at least 2h.
(7), biological filter process: the slurries after cyanogen process falls in biology enter biological filter chamber treatment system, and the treatment time is at least 1h.
(8), qualified discharge: the slurries qualified discharge after the process of biological filter.
In described step (1), the mass ratio of sizing mixing of mine tailings and water is 1:1 ~ 1:10.
In described step (2), the material of micro-hole aerator is stainless steel, pottery or titanium alloy, and the intake of ozone is 2 ~ 8 times of the pollutent quality sum of prussiate and COD in ore pulp.
In described step (3), acid medicine is sulfuric acid, hydrochloric acid, ferrous sulfate or ferric sulfate.
In described step (4), the add-on of hydrogen peroxide reagent is 0.5 ~ 5 times of the pollutent quality sum of prussiate and COD in ore pulp.
In described step (6), fall cyanogen flora be in streptococcus, Staphylococcus, bacillus, brevibacterium sp, pseudomonas one or more bacterial strains composition, nutritive substance is for falling part carbon nitrogen source needed for cyanogen flora and inorganic salt, slurry temperature remains on 20 ~ 35 DEG C, and the material of micro-hole aerator is stainless steel, pottery or titanium alloy.
In described step (7), biological filter chamber treatment system is in series by one or more levels biological filter, water-distributing device and micro-hole aerator is provided with at the bottom of pond, biological filter, it is the active carbon filler layer of biofilm above micro-hole aerator, biofilm bacterial classification is nitrite bacteria and nitrobacteria, and during operation, vapour-liquid ratio is 1 ~ 5:1.
Specific examples:
Certain gold mine cyanogen-containing tailing slag, CN
tfor 413.47mg/kg, Cu
2+for 82.56mg/kg, COD are 187.25mg/kg, other heavy metal ion in addition containing trace.Get 1kg mine tailings and be placed in steel basin, add 1kg water, stirring is sized mixing 30min, then uniform ore pulp of sizing mixing is placed in ozone oxidation groove, pass into ozone and carry out oxidizing reaction 1h, the intake of ozone is 1.46g, then the ore pulp after ozone oxidation is placed in steel basin, add dilute sulphuric acid and regulate slurry pH to 8.0, then the hydrogen peroxide 6mL of 35%, filter after reaction 30min, slurries are passed into biology and fall in cyanogen treatment reactor, cyanogen flora falls in access, pass into air, vapour-liquid ratio 3:1, process 2h, slurries peristaltic pump after process pumps in upstream biological filter, vapour-liquid ratio is 3:1, process 1h.Mine tailings after filtering are carried out toxicity characteristic leaching procedure analysis, and as shown in Table 1 and Table 2, the slurries after being processed biological filter carry out chemical composition analysis to result, and result is as shown in table 3.
Table 1 mine tailings poison leaching test-results one
Note: Biao Zhong analysis elements unit is mg/L, pH value is zero dimension.
Table 2 mine tailings poison leaching test-results two
Note: Biao Zhong analytical element unit is mg/L, pH value is zero dimension.
Table 3 slurry content analytical results
| Analytical element | pH | CN T | Cu | Pb | Zn |
| Numerical value | 8.46 | 0.025 | 0.11 | <0.05 | 0.01 |
| Analytical element | Cd | Cr | Cr 6+ | Ni | As |
| Numerical value | <0.01 | <0.03 | <0.004 | <0.01 | 0.031 |
Note: Biao Zhong analytical element unit is mg/L, pH value is zero dimension.
Compare known with related data in " Hazardous wastes judging standard leaching characteristic identification " (GB5085.3-2007), " integrated wastewater discharge standard " (GB 8978-1996) and " general industrial solid waste is stored, disposal site Environmental capacity standard " (GB18599-2001) respectively by table 1 and table 2 result, mine tailings belong to the Ith class general industrial solid waste.Known from the slurries analytical data of table 3, slurries can reach " Groundwater Environmental Quality standard " (GB/T14848-93) III class water quality standard.
Claims (7)
1. a cyanogen-containing tailing slag administering method, the method comprises the following steps:
(1), size mixing: get mine tailings and add water and to size mixing under whipped state process, size mixing time at least 10min;
(2), ozone Oxidation Treatment: the ore pulp evenly of sizing mixing is placed in ozone oxidation groove, and pass into ozone and carry out oxide treatment from the micro-hole aerator of reactor bottom, the treatment time is 30min at least;
(3), pH regulator: the ore pulp after ozone Oxidation Treatment adds acid medicine and regulates between slurry pH to 7 ~ 9, if the slurry pH after ozone Oxidation Treatment is between 7 ~ 9, can regulate;
(4), hydrogen peroxide oxidation process: regulated the ore pulp of pH value to add hydrogen peroxide reagent under whipped state and carried out oxide treatment, or added hydrogen peroxide reagent and copper sulfate reagent and carry out catalytic oxidation treatment;
(5), solid-liquid separation: the ore pulp after hydrogen peroxide oxidation process carries out solid-liquid separation by the solid-liquid separation method of thickener, settling tank, filter, whizzer, slag after separation enters slag field and stores up or prepare architecture engineering material, slurries after separation turn back to the process of sizing mixing of next round mine tailings, or are further processed;
(6), cyanogen process falls in slurries biology: the slurries after solid-liquid separation enter biology and fall cyanogen treatment reactor, and cyanogen flora and nutritive substance fall in access biology, and pass into air by micro-hole aerator and carry out biology and fall cyanogen process, the treatment time is at least 2h;
(7), biological filter process: the slurries after cyanogen process falls in biology enter biological filter chamber treatment system, and the treatment time is at least 1h;
(8), qualified discharge: the slurries qualified discharge after the process of biological filter.
2. a kind of cyanogen-containing tailing slag administering method according to claim 1, is characterized in that: in described step (1), and the mass ratio of sizing mixing of mine tailings and water is 1:1 ~ 1:10.
3. a kind of cyanogen-containing tailing slag administering method according to claim 1, it is characterized in that: in described step (2), the material of micro-hole aerator is stainless steel, pottery or titanium alloy, and the intake of ozone is 2 ~ 8 times of the pollutent quality sum of prussiate and COD in ore pulp.
4. a kind of cyanogen-containing tailing slag administering method according to claim 1, it is characterized in that: in described step (3), acid medicine is sulfuric acid, hydrochloric acid, ferrous sulfate or ferric sulfate.
5. a kind of cyanogen-containing tailing slag administering method according to claim 1, is characterized in that: in described step (4), and the add-on of hydrogen peroxide reagent is 0.5 ~ 5 times of the pollutent quality sum of prussiate and COD in ore pulp.
6. a kind of cyanogen-containing tailing slag administering method according to claim 1, it is characterized in that: in described step (6), fall cyanogen flora be in streptococcus, Staphylococcus, bacillus, brevibacterium sp, pseudomonas one or more bacterial strains composition, nutritive substance is for falling part carbon nitrogen source needed for cyanogen flora and inorganic salt, slurry temperature remains on 20 ~ 35 DEG C, and the material of micro-hole aerator is stainless steel, pottery or titanium alloy.
7. a kind of cyanogen-containing tailing slag administering method according to claim 1, it is characterized in that: in described step (7), biological filter chamber treatment system is in series by one or more levels biological filter, water-distributing device and micro-hole aerator is provided with at the bottom of pond, biological filter, it is the active carbon filler layer of biofilm above micro-hole aerator, biofilm bacterial classification is nitrite bacteria and nitrobacteria, and during operation, vapour-liquid ratio is 1 ~ 5:1.
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Cited By (4)
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| CN105541019A (en) * | 2015-12-28 | 2016-05-04 | 天津凯英科技发展有限公司 | Treatment method of high-concentration oil-containing cyanide-containing wastewater |
| CN106269785A (en) * | 2016-07-29 | 2017-01-04 | 山东国大黄金股份有限公司 | A kind of method of baking cyaniding tailings clean conversion |
| WO2017120634A1 (en) * | 2016-01-15 | 2017-07-20 | Global Aquatica Pty Ltd | Processes for treating acid producing waste rock |
| CN109675914A (en) * | 2019-01-30 | 2019-04-26 | 中城华宇（北京）矿业技术有限公司 | A kind of cyanidation tailings method for innocent treatment and device |
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Cited By (5)
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| CN105541019A (en) * | 2015-12-28 | 2016-05-04 | 天津凯英科技发展有限公司 | Treatment method of high-concentration oil-containing cyanide-containing wastewater |
| WO2017120634A1 (en) * | 2016-01-15 | 2017-07-20 | Global Aquatica Pty Ltd | Processes for treating acid producing waste rock |
| CN108883444A (en) * | 2016-01-15 | 2018-11-23 | 环球阿卡迪卡有限公司 | For handling the method for generating the barren rock material of acid |
| CN106269785A (en) * | 2016-07-29 | 2017-01-04 | 山东国大黄金股份有限公司 | A kind of method of baking cyaniding tailings clean conversion |
| CN109675914A (en) * | 2019-01-30 | 2019-04-26 | 中城华宇（北京）矿业技术有限公司 | A kind of cyanidation tailings method for innocent treatment and device |
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