Copper other (product processing, management, sewage purification, etc.) (1)

(one)
Copper Mine recording processing plant is selected from copper, iron ore processing plant large, vulcanization method using the copper flotation, magnetic separation method is selected from iron. Due to high oxidation rate, high binding rate, large mud content and large amount of oil, the high suspended solids content is difficult to settle naturally. The annual discharge of sewage is about 4 million tons. After natural sedimentation, it is discharged into Daye Lake. .
The main plant of the plant is equipped with 6 sets of 2.7×3.6M lattice ball mills , 6 sets of 2M high-grade spiral classifiers, 66 sets of 2.7M ³ ring-length long-term flotation machines, 168 sets of 5A flotation machines and 11 sets of sand pumps. 6 sets of 1500 Oersted permanent magnet magnetic separator and 6 sets of 400 kW synchronous motors. The noise from these devices, the constant magnetic field and the harmful gases generated by the flotation reagents cause comprehensive pollution, which directly affects the health of workers.
1. Composition, hazard and treatment of sewage (1) The composition of the selected plant wastewater is mainly copper, iron concentrate concentrated overflow water, tailings water and flushing water, etc., copper concentrate thickener overflow water (#1) The composition of the overflow water ( ^# 2) with iron ore thickener is listed in the table below.

(2) Hazard Suspended matter The sewage contains a large amount of colloidal contaminants such as suspended solids and copper-iron compounds, which makes the water turbid and becomes "red water". It is mainly caused by two kinds of iron compounds. One is iron hydroxide, ie Fe(OH) ₃ , and the other is iron oxide, ie Fe ₂ O ₃ . After the sewage containing these two compounds is discharged, a gel or floc is formed. When suspended in water, it will Harmful to fish and other aquatic organisms, they can form flocculated matter covering the bottom of the lake, destroying benthic plants and fish eggs. Over time, these flocs gradually thicken, which makes the lake bed increase, the water system is disordered, and the excretion is not smooth.
Copper Ion It can be clearly seen from the above table that the copper and iron in the sewage exceeds the standard by several times. When copper is present in an ionic state, it is most toxic, its chemical properties are stable, and it cannot be biodegraded. Copper ions can also be absorbed and enriched by passive plants, poisoning the human body through the food chain, causing brain diseases and hematuria, which can be fatal in severe cases. U•Forstner et al. have studied the relationship between copper concentration and human reception (Figure 1). Copper ions also have an obvious effect on fish. When the copper content in the soil is higher than 20 mg/L, the wheat will die.

figure 1
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The main hazard of butyl xanthate is to make the embryo develop teratogenic and show strong toxicity to the fish eggs. It is also reported in foreign countries that xanthate can cause mutations in mammalian and human chromosomes.
Pine oil Oil Pine oil and yellow medicine can also produce a significant synergy and increase toxicity.
Sodium sulfide is mainly derived from H ₂ S. It is believed that when the sulfide concentration exceeds 2.0 mg/L, it poses a chronic hazard to aquatic organisms.
In summary, the various components in the ore dressing wastewater of the Tonglushan Mine have caused obvious harm and potential threat to aquatic organisms and human body.
(3) Governance 1 Make full use of backwater and reduce emissions The fundamental and economic solution to solve the problem of sewage is to recycle and reduce emissions so that harmful substances do not pollute the external environment. With the circulating water treatment process, the amount of water returned can reach 50%, which does not affect the magnetic separation effect.
2 Strengthen production management, reduce the amount of oil and medicine to start with production management, establish a normal production order, set reasonable technical operating conditions, determine appropriate pharmaceutical dosage indicators, and implement conservation awards to make the consumption of pine oil from 1979 Year after year, the copper content has also decreased year by year, as shown in Figure 2 and Figure 3.

Figure 2 Figure 3

3 Study on the removal of pine oil The biological treatment method - the test using the algal symbiosis system to purify the pine oil showed that the removal effect was good. The COD of the water outlet is 19~87mg/L, and the BOD is 15~24mg/L, which are lower than the national discharge standard. From the actual effect, the concentrate overflow water and the domestic sewage in the mining area are mixed into the fish pond (sedimentation tank). Because the domestic sewage promotes the reproduction and growth of aquatic organisms, the pine oil can be naturally enriched by water enrichment. [next]
Activated carbon adsorption method - The test results of adsorption of pine oil show that the national emission standard can be achieved whether it is primary or secondary purification. The main problem that currently exists is that the economy does not count.
2. Noise generation, hazard and control of the main plant of the plant (1) Sound source As mentioned above, there are hundreds of electromechanical equipment such as ball mills and synchronous motors in the main plant of the plant. These devices generate noise in different frequency bands, especially The low noise causes strong noise pollution in the main building, and the noise is as high as 110 decibels or more.
(2) Hazards According to the majority of people, hearing loss (such as so-called noise deafness), long-term insomnia, emotional instability, irritability and memory loss and other neurasthenia.
(3) Control assumptions It is best to take active measures to reduce noise sources, and negative measures such as sound insulation, sound absorption, vibration isolation and damping. Reducing the noise source reduces the noise of the electromechanical device itself, so that it emits as little noise as possible. The method of sound insulation is to pass the emitted sound wave through the porous medium to cause vibration and friction, and the heat is lost, so that it is exhausted. May spread less outward.
3. Harmfulness of harmful gases and constant magnetic fields in the main building and control of the human body in the Tonglushan Mine Concentrator. In China, there are only a handful of added xanthate, pine oil and sodium sulfide. oxidation, decomposition and evaporation process produces a large amount of harmful gases, particularly hydrogen sulfide gas irritating. In the hot season, the chemicals evaporate quickly and the ventilation is not good. The workers will have short-term loss of appetite and other reactions. After "adaptation", there will be diseases such as vision loss, throat and bronchial inflammation. Automated dosing and drug adjustment can be adopted to avoid direct contact with the agent; find the optimal drug delivery value and reduce the amount of addition; increase ventilation facilities in the plant to speed up air convection; and mobilize each operator to wear protective masks and other methods to control.
There are six 1500 Oersted permanent magnet magnetic separators installed in the main plant of the factory. It has a certain influence on people who have long lived in the earth's magnetic field with an intensity of 0.28~0.71 Oersted. Although there are many reports on the use of constant magnetic fields to treat diseases, long-term exposure to a strong magnetic field of 1500 Oerst can also cause headache, dizziness, tinnitus, dizziness during standing, irritability and rapid heart rate, insomnia and hair loss. And other anomalies.
At present, the control of a constant magnetic field is under study. When possible, it is a good idea that the operator should try to stay away from the magnetic field and not expose the body to the magnetic field for a long time.
(two)
The Dahe Copper Mine in Nanyang District of Henan Province is located upstream of the agricultural “Erlangshan” Reservoir in Tongbai County. Due to geographical constraints, the plant wastewater (concentrate filtered water, tailings dam drainage and other industrial wastewater) must be discharged into the reservoir.
Processing plant was selected as the copper ore, zinc complex multi-metal sulfide ore flotation separation process using cyanide-free separation. The dosage forms are: sodium sulfide, zinc sulfate, sodium sulfite, copper sulfate, lime, xanthate and ^# 2 flotation oil. The water quality check results of the selected plant wastewater indicate that certain harmful components (such as sulfides and xanthates) in the wastewater exceed the national standards for discharge into the surface water, which will pollute the reservoir water with low fluidity. In order to prevent pollution, protect agriculture, aquaculture and mine production and domestic water sources, Dahe Copper Mine systematically conducted research on the use of wastewater from the selection of plants. In 1973, a small-scale experiment was carried out. Sulfur mixed selection - the process of zinc and sulfur separation. The wastewater is completely returned to the beneficiation process through the adjustment of the process flow, and the selection index is close to the fresh water selection index.
However, since the wastewater used in the small test was clarified and filtered, the suspension was removed; in addition, according to the water quality analysis, the concentrations of copper and lead ions affecting the separation of copper and zinc were not stabilized at the same level, and whether long-term recycling would affect the separation effect. . Small tests are difficult to ascertain due to conditions, so industrial tests are required.
The first industrial test The process of testing in the mine selection plant in December 1979 was limited by the site conditions at the time. It was the process of using priority float copper and then floating zinc (the sulfur product was not recovered at the time). The wastewater used is from the nearly abandoned, small-capacity old tailings pond's stilling pool. Due to the small storage capacity, the wastewater discharged into the warehouse is less than 20 hours, which is not a good natural purification.
Tests show that due to the short residence time of wastewater in the tailings pond, the natural purification is insufficient, although the amount of sodium sulfide is increased, the amount of xanthate and ^# 2 oil is reduced, and the amount of lime is controlled, but the various groups brought back by the return water There are still some impacts on the mineral processing technical indicators. The copper concentrate has a copper reduction of 2.53%, the zinc content increased by 2.82%, and the copper recovery rate increased by 1.07%. However, the copper concentrate quality does not reach the mine quality standard; the zinc concentrate contains zinc. The reduction of 6.57% and the zinc recovery rate increased by 14.68%. Although many times of debugging, failed to achieve satisfactory results. [next]
The second industrial test was due to the short residence time of the waste slag in the tailings pond in the previous test, and due to the limited production conditions, the backwater could not be recycled for a long time. After another new tailings pond was put into use, Industrial trials of backwater utilization were carried out from October to December 1980.
The process of this industrial test is the process of preferential float copper-zinc-sulfur mixed--zinc-sulfur separation. In the test, for the sake of comparison, the return water and the new water were alternately used. The technical indicators of the test are shown in the table below. The test results show that the wastewater is kept in the tailings pond for a sufficient residence time and is properly investigated for the amount of the medicament. The use of recycled water can achieve satisfactory results.

Industrial production for backwater use On the basis of small-scale, industrial trials, industrial production that was not used back began in July 1982. Industrial tests using backwater use have proven that all wastewater can be returned to the plant selection process and no longer discharged.
In August 1981, the beneficiation process was commissioned at the plant. The purpose was to reduce the process of zinc impurity in the copper concentrate. The purpose was to reduce the content of zinc impurities in the copper concentrate to improve the quality of the copper concentrate. The commissioning was mainly to increase the proportion of sodium sulfide and reduce the proportion of zinc sulfate and sodium sulfite. After debugging, the copper grade of copper concentrate is increased by about 3%, and the zinc grade is reduced from 16-20% to less than 15%.
In the ten months before and after the use of backwater, the technical indicators of the eight months with similar ore properties were selected. Compare Figures 4, 5, and 6. It can be seen from the figure that the long-term recycling of the backwater by the plant can obtain technical indicators similar to those of the new water production. It proves that backwater can be used well in industrial production.