What Do You Need to Know about the Tailing's Treatment Process?
2019-08-02 18:32:17xinhai
The tailings are treated by tailings dam stockpiling in concentrators. The residual toxic agents, waste water and heavy metal ions in the process of ore dressing will not only cause pollution and ecological damage to the surrounding environment of the mine, but also increase the potential safety hazards of tailings dam and induce landslides, debris flows and dam breaks of tailings dam and other accidents. Therefore, tailings treatment has been highly valued.
Tailings re-processing, Tailing dry stacking, and tailings filling goaf. Below we will explain these three parts separately.
Although the content of useful components in tailings is relatively low, we can reprocess tailings by the advanced technology and reasonable process to recover the useful components in tailings to a greater extent, so that we can fully recycle and reduce resources as well as reduce the final production of tailings and alleviate the pressure on the environment.
1. Using a flotation process to process tailings containing minerals such as colemanite, zinc oxide, and apatite.
Due to the development of new pharmaceuticals and new processes, some tailings with relatively simple process, especially old tailings, can be reprocessed by flotation to obtain recyclable concentrate ore.
2. Using the new gravity separation equipment to recover the fine-grain minerals in the tailings.
Many traditional gravity separation equipment can be applied in fine-grained and ultra-fine tailings reprocessing after being invented and perfected, such as vertical centrifugal concentrators, composite stand shakers, composite field centrifuges, and so on.
3. Microbial Treatment and Leaching Solution in Tailing Mining
Microbial treatment and leaching Solution mainly use the biochemical action of microorganisms to improve the tailings properties, which extract harmful metal ions in tailings by means of microbial leaching or mineralization to avoid environmental pollution.
Tailings are the main components of industrial solid wastes, which have low content of useful components and cannot be used for production. Tailings treatment is one of the important links in mine production, but what are the methods of tailings treatment, do you know?
In the tailings processing stage, the slurry often contains a lot of water, which would be likely to lead to the tailing dam failure. Therefore, in the tailings processing plant, concentration of tailings is also one of the important parts. The common tailings dewatering process includes:
1. Concentration process with hydrocyclone as the core in tailing dry stacking
As a kind of equipment for solid-liquid separation using centrifugal force, the hydrocyclone has the characteristics of small footprint and high underflow concentration. The concentration process mainly uses hydrocyclone and thickener to form a series or closed circuit to obtain high concentration.
2. Tailings filtering with filter press
In dealing with gold tailings, filtering dewatering is also used. This method has traits that low water content, recyclable filter liquor and so on. However, the single filter press has a lower capacity, which can hard deal with mineral tailing dewatering in large scale.
Tailings dry stacking is a new technology with dewatering hydrocyclone, high-efficiency high-frequency dewatering screen, high-efficiency deep-cone thickener and other patent equipment. It can reduce water content in tailings under 15%, saving investment, and also avoiding environment pollution effectively.
Tailings sand filling in the goaf is a method dealing with tailing sands, which can protect terrain, reducing the cost of tailings dam and so on. Now the main methods of tailings filling in the goaf are the two as follows:
1. Full tailings cementing filling technology
Full tailings cementing filling technology is the method using the mixture of dewatering tailings, cement, and coal ashes with hardness between 1~2 MPa filling in the goaf with pipes, in order to filling in the goaf.
2. Unclassified tailing backfilling technology by high water consolidation
Unclassified tailing backfilling technology by high water consolidation is similar to the whole tailings cement filling, but the difference is that except that the unclassified tailing backfilling technology by high water consolidation uses the high-water material as the cementing material instead of cement. This method uses a kind of materials (mainly aluminate, sulphoaluminate) and another kind of materials (mainly anhydrite, quicklime and coagulant), which needed to be transported respectively, and mixed before filling at a fast condensation rate.
Bulgaria 1000t/d lead-zinc mine tailings dry stacking project
Project background:
The original treatment method of tailings of this project adopted tailings wet drainage method. The tailings flowed into tailings pond through pipelines. It was a side-mountain tailings pond with small inventory, low flood regulating capacity, poor flood control conditions, and complex management and maintenance, dam break phenomena in the later stage.
Xinhai solution:
According to the tailing output and the basic properties of tailing pulp, Xinhai made a series of scheme designs and finally determined the appropriate tailings dry stacking process, which was equipped with hydrocyclone, efficient deep cone thickener, filter press, high-frequency dewatering screen and wear-resistant slurry pump as supporting equipment for the tailings dry stacking process.
Project result:
The tailings dry stacking process alleviated the problem of water use, and achieved the water recycling. Finally, the return water of tailings dry stacking was less than 15%, 80% of which were returned to the plant for reuse.
Yunnan 4 million t/a hematite ore tailings reprocessing project
Project background:
The iron concentrate quantity of this plant was 264,300 tons, and the iron concentrate grade was 64.00%, the iron concentrate recovery was up to 82.80%. In 2006, the plant was expanded to 4 million t/a. and the quantity of the iron concentrate reached 1,864,000 tons, but the grade of the selected raw ore was decreased to 35%, which failed to reach 39.41% as the designed target.
Xinhai solution:
After analyzing the composition of tailings, Xinhai Mining decided to adopt the strong magnetic separation process (single coarse and single cleaning). When the iron grade of secondary magnetic separation tailings was 20.00% - 30.00%, the concentrate grade reached 52.00%, the tailings grade was 13.00% ~ 18.00%, and the total tailings grade was decreased to 14.00%.
North Korea 2500t/d gold tailings flotation project
Project background:
There were more than 10 million tons of gold tailings in this project. The average grade of gold in the tailings was 1g/t. The main recoverable valuable element in the tailings was gold. Other harmful elements contained a small amount without any environment pollution.
Xinhai solution:
Xinhai Mining adopted "one closed-circuit grinding - one coarse, three scavenging and three cleaning flotation - two stages mechanical dewatering process ". Besides, Xinhai Mining adopted a series of high-quality equipment for this project, such as wear-resisting hydrocyclone, wear-resisting slurry pump, cylinder energy-saving overflow ball mill and high efficiency agitation tank, so as to realize the efficient utilization of tailings resources.