I. Introduction
*********** limited liability company located in the delta town of Hulun Buir City, Istanbul, two existing beneficiation plant, daily processing capacity of 900 tons (600 tons +300 tons), lead-zinc ore processing ore The original ore grade is about 4% of lead plus zinc, the raw ore contains 7-8% sulfur, and the original ore contains 50-60 g/ton of silver . **** metal mining companies are more mineral species, wherein the main metallic minerals galena, pyrite, sphalerite and arsenopyrite. The main recovered elements are lead, zinc and silver, and the zinc tail is the final tailings.
Second, the status quo of the production of the concentrator, the existing problems and the necessity of transformation
1. Production status
The lead and zinc concentrates of the 600 ton/day concentrator are dehydrated in two stages, first concentrated and then filtered and dewatered. Concentrate of lead concentrate was concentrated using a 9 m central drive concentration cell and then filtered using a 12 m2 cylindrical filter. The zinc concentrate was concentrated using a 9 m central drive concentrating tank and then filtered using a 12 m2 cylindrical filter. Each concentrated filtered water enters the tailings pond. The flotation tailings all enter the tailings pond.
The lead and zinc concentrates in the 300 ton/day concentrator are dehydrated in two stages, first concentrated and then filtered and dewatered. The concentrate concentrate was concentrated using a 3.6 m central drive concentrating tank and then filtered using a 3 m2 cylinder filter. The zinc concentrate is concentrated using a 6 m central drive concentrating tank and then filtered using two 3 m2 cylinder filters. Each concentrated filtered water enters the tailings pond. The flotation tailings all enter the tailings pond.
2, the problems and the necessity of transformation
(1) At present, the dam height of the tailings dam is increasing year by year, which is higher than the road surface height of the original mining area. If it continues to increase, it may cause hidden dangers to the safety of the tailings dam.
(2) By examining the concentration of tailings in the plant, it is concluded that the concentration of mine tailings is relatively low, only about 15%, plus the lead and zinc overflow water of the two plants, the concentration of pulp in the tailings dam is very low. Moreover, the sedimentation rate is slower. Eventually, the volume of the tailings dam will drop rapidly.
(3) In the past, the ore dressing wastewater of the mine has never been recycled. It is intended to use the overflow water and filtered water dewatered from the tailings to produce zinc-selected brewing water and clean floor water. Partial reuse, that is, reducing wastewater discharge and reducing production costs.
Third, the program selection
Program | Option One | Option II | third solution | Option four | |
Tailings dam expansion | New tailings dam | Tailings filtered and exported | Tailings filtered after dry heap | ||
Total investment estimate (ten thousand yuan) | equipment | 193.5 | 193.5 | ||
Civil engineering | 100 | 150 | 125 | 125 | |
other | 50 | 50 | 11.5 | 11.5 | |
total | 150 | 200 | 330 | 330 | |
Impact on forest environment | Minor impact | influential | no | no | |
Site selection | not easy | not easy | easy | easy | |
Renovation investment costs | least | less | Higher | Higher | |
Production, sales and operating expenses | Lower | Lower | Higher | Higher | |
Production management experience | Have some experience | has experience | has experience | has experience | |
safety | Have certain hidden dangers | Safer | Safety | Safety | |
Construction period | Shortest | Longer | Longer | Longer | |
Whether there is a factory that can use tailings | no | ||||
transportation cost | Higher | ||||
For future development (such as tailings treatment and utilization) | Conducive to future use | Conducive to future use | Comprehensive utilization | Conducive to future use | |
Program | Poor | general | general | better | |
The final option is four: the tailings are filtered and dried.
Fourth, tailings dehydration transformation program
Combined with the geographical conditions of the mine, the amount of ore, the amount of water supplied, the capacity of the tailings pond, and other factors, the company has determined the production organization plan for the annual production of the 300T plant and the discontinuation of the 600T plant in winter. At the same time, considering the factors of reducing energy consumption, reducing the labor intensity of workers, and improving the working environment, the final scheme of the tailings dewatering project is: using a NT-24 peripheral rack-driven concentrator for a period of concentration, using two HTG-45 meters. 2 The ceramic filter is subjected to two-stage concentration (filtration) to finally produce tailings ore with a moisture content of about 10%, which is then transported by car to the tailings storage.
According to the design requirements, the daily processing capacity of the concentrator is 900 tons/day, and the tailings ore amount is 850 tons per day.
Thickener selection
(1) Calculate the area of ​​the thickener:
F=Q/q, Q=850 tons/day, q=1.0-2.0 tons/meter 2. Day
F = 425 ~ 850 m 2
(2) Calculate the diameter of the thickener:
D=1.13√F, D=23.29～32.94 meters
Check the "Mineral Design Manual", combined with the tailings production capacity of 35.42 tons / hour, as well as the mine production plan and the low temperature of the winter forest area, so choose a NT-24 peripheral rack drive type concentrator to meet the production requirements.
Filter selection
In combination with the production practices of similar mines, more and more mines use advanced ceramic filters instead of filter cloth vacuum filters. Therefore, the company chose ceramic filters for tailings filtration.
F=Q/q, Q=850, ton/day, q=3×6×0.6 ton/m 2
F=78.70 m 2
Therefore, two HTG-45 m 2 ceramic filters can be used to meet the production requirements.
V. Introduction to tailings dehydration transformation plan
The process is two-stage concentrated filtration. The flotation tailings are concentrated from the flotation plant to the concentration tank for concentration. The bottom of the concentration tank flows from the ceramic filter to the ceramic filter for filtration. The tailings are filtered and transported by car to the old tailings pond. The process is simple and applicable, and no new tailings pond is needed.
Tailings dehydration process flow chart
In combination with the special climatic conditions of the forest area, in order to prevent the winter temperature from being too low, the concentrating equipment used is the NT-24 peripheral rack-driven thickener. This is a relatively mature mineral processing equipment commonly used in domestic mines. The ceramic filter is a high-tech product integrating micro-porous ceramics, mechanical, ultrasonic cleaning and automation control. It is a new type of high-efficiency material dewatering equipment . It uses microporous ceramic material as the filter medium. The capillary effect principle is applied. The water can pass through and the ore particles cannot pass through the filter medium. There is no vacuum loss during the whole filtration process, and less energy is needed. The consumption can ensure that the filter is operated under a vacuum, and the filtration efficiency of the device is greatly improved. The utility model effectively solves the defects that the filter device using the filter cloth as the filter medium has low productivity, high filter cake moisture, high energy consumption and high maintenance cost, and the main features are as follows:
1. The vacuum is high and the filter cake has good drying performance.
2. The filtrate is clear and transparent, the working environment is clean and pollution-free.
3, using microcomputer control, high degree of automation, continuous operation, less maintenance work, equipment effective utilization rate of up to 95%.
4. Compared with other filtration systems, energy consumption is saved by more than 90%.
5, no need for expensive filter cloth, almost no spare parts consumption, low operating costs.
6. The equipment is compact in structure and low in installation cost.
The Jiangsu Yixing Non-Metal Chemical Machinery Factory won the bid for the ceramic filter of our company is a key high-tech enterprise recognized by the Ministry of Science and Technology. The ceramic filter produced by it has 6 invention patents. Technically reliable.
Tailings dewatering plan layout
Sixth, auxiliary projects
The installed power of tailings dewatering is 80 kW, and the power supply is connected to the power distribution room of the plant. The water supply utilizes the existing water supply system, and the heating is provided by the newly built boiler, and the drainage is discharged directly into the tailings storage. Machines, electricity, repairs, etc. are maintained by existing plant selection machines, electricity, repairs, and tailings transportation is shipped from the company's fleet to the tailings storage.
7. Occupational safety and health and environmental protection
Our mine already has more mature mining and selection technology in China. The existing industrial sites, water and electricity construction conditions can meet the requirements of technical reform. Therefore, the scope of occupational hazards has not been expanded, and new tailings dewatering projects are underway. The nitric acid used in the ceramic filter cleaning filter plate can provide pre-employment training for workers during the production process, providing necessary labor protection measures and can be controlled during the production process.
This transformation has no damage to the current environment, and can alleviate the potential damage to the surrounding environment of the existing tailings pond and extend its service life. It is a concrete embodiment of implementing the sustainable development strategy.
Eight, technical and economic analysis
1. Labor quota
The mine work system is: 330 days, 3 shifts and 8 hours work system. In the plant selection, a new tailings dewatering section was added, with 6 new dehydration operators, 1 boiler worker, and a wage of 9,000 yuan per person per year.
2. Total project investment and fund raising
The total investment of the project is 4.106 million yuan, all of which are self-raised by the enterprise.
Project | Name | Units and specifications | Price (ten thousand yuan) |
Take earthwork | Concentrated filtration plant takes earthwork | 15051.75 m3 | 35.318 |
equipment purchase | NT-24 thickener | 1 set | 27.5 |
HTG-45 m 2 ceramic filter | 2 sets | 166 | |
Civil engineering and installation | Concentrated pool insulation room | 27×27×4 (m) | 63.005 |
Concentration pool | Φ24 (m) | 47.086 | |
Filtration plant | 27×15×9.5 (m) | 56.674 | |
electric | Concentrator, filter distribution | 5 | |
other | 10 | ||
Total investment | 410.6 | ||
3. Project implementation schedule
The infrastructure period was 3 months and was put into operation in November 2007.
4. Cost estimate
Cost item | unit cost (yuan/t) | Annual cost (yuan/a) | Remarks |
Purchased auxiliary materials, pharmaceuticals | 2.1 | 315000 | |
Outsourced fuel and power | 1.5 | 225000 | |
Wages and benefits | 0.42 | 63000 | |
Repair fee | 0.35 | 52500 | |
Other fees | 0.2 | 30000 | |
total cost | 4.57 | 685500 |
Nine, conclusion
Based on the needs of sustainable development of mines, our company looks to the future. According to the actual situation of our company's ore dressing, we use advanced production technology and equipment to dewater the tailings and dry them in the existing tailings dam to protect the forest environment. . While realizing the company's economic benefits, and harmonious development with the forest area, it will certainly achieve good social benefits.
Jiangsu Zhongcan Marine Equipment Co.,Ltd. , https://www.anchorchainzc.com