The testing data provided by the ore samples in mineral processing tests is an important basis for the design of mineral processing technology. In order to make the data of mineral processing tests more accurate, there are many requirements for the selection of ore samples. Today I will take you to understand how to select representative, appropriate granularity, and different types of ore samples.
How to select representative ore samples
When selecting ore samples, it is generally necessary to consider the long-term development of the mine and whether it is consistent with the nature of the ore deposit.
Consider long-term development
The selected ore samples should not only represent the current situation of the ore deposit but also consider the situation of the ore in the mine for several years, and expect to remain basically consistent. Generally, ore samples that are highly representative of the whole ore deposit or the mining area should be selected. If the sampling conditions are insufficient, the main ores that will be processed in the next 5-10 years of the plant can also be selected as test samples, and the ore samples of non-ferrous metal mines and chemical mines should be more than 5 years.
The basic information of the ore sample should be basically consistent with the ore deposit. The evaluation standards include the chemical composition of the ore, mineral composition, structure, and texture, the existence of useful and harmful elements, and the distribution and existence of the components available for comprehensive recovery.
Select ore samples with physical and chemical properties consistent with the ore deposit and mining range. The physical aspects include the density, hardness, looseness, compressive strength, viscosity, humidity, etc. of the ore, and the chemical aspects include the degree of oxidation, soluble salt content, etc. At the same time, the selection of samples still needs to consider the future mining range of the ore deposit and keep them basically consistent.
Finally, consider the average grade of the ore sample’s main components, the grade fluctuation status, and the proportion of different types and grades of minerals, which should be roughly the same as the proportion of the same type of ore reserves in the mine or the proportion of ore sent to the dressing plant within several years.
Take more samples
The selected ore samples can include ore samples from different positions such as the ore body bottom plate, surrounding rock, and intercalated rock, in addition to selecting the ore deposit. The types, components, and proportions of these samples should be basically consistent with the actual situation during mining.
How to determine the particle size of ore samples
In the selection test of ore, there is a certain requirement for the particle size of the mineral sample. The particle size of the laboratory mineral sample is usually 50-0mm or 100-0mm. In the semi-industrial and industrial experiments, the sample particle size is determined according to the requirements of the selected mineral processing method, process flow, and laboratory equipment. The requirements for sample particle size in tests such as similar function index tests follow the specific requirements put forward by the experimental unit.
How to select different types of ore samples
Usually, the selected ore samples are collected in stages, and a large number of ore samples are selected from the early mining areas of the ore deposit, and a small amount of ore samples can be selected from the later areas as verification samples. If the ore deposit has a small amount of ore reserves and a short production time, there is no need to consider sampling in stages. The specific ore selection should also pay attention to:
- Ore samples should be selected from different ore bodies and ore sections to meet different mineral processing experiments. If it is not possible to collect separately during the actual sampling process or there is no need to collect separately, mixed ore samples are used for subsequent mixed ore sample mineral processing experiments.
- When the material composition characteristics and ore properties of the ore differ greatly, samples should be sampled according to their different types and grades to meet the mineral processing experiments of single samples or mixed samples later on.
- When the differences in the content of the main components of the ore and the beneficial and harmful components of the accompanying minerals are large, samples of different ore deposit levels should be selected according to their types and grades, combined with the mining design plan, and different mineral processing experiments are carried out.
- To make more reasonable use of limited mineral resources, if there is a certain amount of outcrop ore in the ore deposit, it should be sampled separately, and the possibility and rationality of its recovery and utilization should be comprehensively evaluated.
- If there are valuable, rare elements, and other components available for comprehensive recovery in the ore body, surrounding rock and intercalated rock and veins, representative ore samples should be selected for comprehensive recovery experiments based on the study of the occurrence state and spatial distribution of their associated components.
- Samples of ore body bottom plates, surrounding rocks, and intercalated rocks should also be selected in a certain proportion for mineral processing experiments. In addition, a certain number of high-grade ore samples and near-mine surrounding rock samples should be taken to facilitate the experimental research unit to adjust the grade deviation of the ore samples that may occur or meet the temporary needs during the experiment process.
Through the above methods, we can select different types, more representative, and more suitable ore samples for mineral processing experiments, providing direct basis for the reasonable determination of mineral processing design, equipment selection, product scheme, technical and economic indicators, and also providing data basis for the smooth achievement of design indicators and economic benefits after the selection and mineral processing plants are put into operation. Therefore, in order to obtain accurate basis for mineral processing tests, it is recommended to consult professional institutions or expert opinions when selecting ore samples, and specialized testing and research units shall undertake the mineral processing tests to obtain scientific and accurate data for mineral processing tests.