The flotation method is one of the widely used beneficiation processes at present, and the flotation process flow needs to be determined through flotation test, because in the flotation process, not only the selection, dosage and dosing time of flotation reagents need to be considered, but also the air volume, pulp concentration, PH value and other issues need to be considered. Therefore, the flotation test is related to various production indicators, and more related to the benefit of the concentrator.
So, what are the steps for a complete flotation test? In fact, it only needs to draw up a plan, prepare for the test, and conduct flotation test.
Firstly, the ore properties are studied according to the ore samples sent by the customer, and the flotation test scheme is preliminarily prepared in combination with on-site practical experience and professional knowledge.
Preparations before flotation test
1. Sample preparation
The particle size of flotation test is generally required to be less than 1-3mm. The particle size in this range is suitable for the feed particle size of the ball mill used in flotation test, and can also ensure the representativeness of the sample. Therefore, firstly crush the ore sample to make it reach the required particle size. The crushed sample is evenly mixed and divided into several samples, each containing about 500-1000g. For low grade ores, the single content can be increased to 3000g.
Attention shall be paid to avoid sample contamination during sample preparation, and oxygen isolation measures shall be taken for minerals easy to be oxidized.
2. Preparation of flotation reagents
Flotation reagents are particularly important in the flotation process, which need to be prepared in advance and well preserved to keep them active. Generally, first check whether the medicament is within the shelf life to ensure its availability. Second, store it in a dry container and in a cool place before use.
3. Preparation of grinding machine
The laboratory should have a variety of grinders of different sizes to ensure that samples of different doses can be grinded.
4. Preparation of flotation machine
Small mechanical stirring flotation machines are basically used in the laboratory. Several small-sized single cell flotation machines can be selected, such as 0.5L, 0.75L, 1.0L, 1.5L, 3.0L, etc.
5. Flotation water
Generally, the tap water in the area where the laboratory is located is used for experiments. After the main process conditions are determined, the water source that may be used by the concentrator in the future will be used for verification.
6. Prepare clean instruments and tools
Flotation test mainly includes pre test, condition test, closed circuit test, intermediate test and industrial test. The main purpose is to determine the general flow and indicators of ore flotation, and finally determine the flotation conditions.
The flotation test process generally includes grinding, slurry mixing, flotation (foam scraping) and target product treatment.
1. Grinding
First, empty the mill for cleaning. Then the grinding operation is carried out. In this process, it is necessary to pay attention to whether the speed of the grinding machine is normal, whether the operation is stable, whether the grinding sound is normal, etc., and accurately record the grinding time. At the end of grinding, the slurry shall be flushed into the ore receiving container with clean water. Clean the mill after all are poured out.
2. Mixing and mixing
A certain amount of flotation reagents are added into the stirring tank in batches for slurry mixing and stirring, so as to promote the suspension of mineral particles and their uniform dispersion in the flotation tank, promote air dispersion, make the mineral particles fully contact with bubbles, and ensure the flotation effect.
3. Flotation foam scraping
Ensure the inflation volume is stable, and continue to inflate and stir. Adjust the amount of foaming agent, the height of pulp page, and stably scrape out a certain amount of high-quality bubbles. The thickness of foam layer of laboratory flotation machine is generally controlled at 25-50 mm. During the operation, as the foam is constantly scraped out, the slurry level of the tank body keeps dropping. At this time, water is added without affecting the slurry PH to ensure that the foam can be scraped out continuously. At the beginning and end of the foam scraping process, the pH value and temperature of the pulp must be measured and recorded to prepare for later analysis. After flotation, dump the tailings pulp and clean the flotation machine.
4. Target product treatment
The pulp discharged from the flotation machine needs to be dehydrated and dried. After drying, the product should be weighed and sampled for chemical analysis.
After the above three steps, a complete flotation test was completed. Xinhai reminds you that the flotation test is related to the process flow and beneficiation index in the later production, and it needs to find a professional manufacturer to do it.
