How to throttle resources for ball mill

 Nowadays, with the continuous development of social productivity, green energy saving has become the theme of today's society, and various equipment has been continuously improved to save energy and reduce expenditure, especially in the heavy industry industry. It's easy to say, but for mining, power consumption is a big problem. Therefore, in response to similar problems, we propose two improvements, one is the equipment itself, and the other is to improve the operation of the process.

On the one hand, resource throttling of the ball mill is very important. First of all, when designing the ball mill, full consideration must be given to the accessories and devices to save power and reduce consumption. In the design of the ball mill, considering the purpose of energy saving and consumption reduction, a new type of transmission system is specially designed, and a planetary gear reducer is used for transmission, which changes the traditional transmission layout and greatly improves the working efficiency of the motor. This is one of them. Design advantages. In addition, when designing the ball mill, the bearing, drive mode, and liner of the ball mill also added innovations and played a great role.

Another aspect is the process operation. The process is continuously optimized. The three main aspects are the selection of the process flow, the topping method of the steel ball, and the stable and safe operation. Continuously optimize.

The above is what we need to improve. Starting from these aspects to improve equipment to save resources is also a direction we need to continue to develop.

The "hidden rules" of ball milling

 Corresponding proportioning of the ball mill, so that it can crush minerals to the greatest extent, and meet the requirements of mineral crushing and grinding. The quality of mineral crushing can directly affect the efficiency of milling, and ultimately affect the overflow output of the ball mill. The level of ball loading can directly affect the crushing effect. These parameters are mainly affected by the specifications of the ball mill, the internal structure of the ball mill, and the fineness of the product.

The ball must have sufficient impact force so that the ball has sufficient crushing capacity to handle the material, which is directly related to the diameter of the steel ball.

The number of impacts of loading the ball must be enough so that the ball can crush the material. The average ball diameter and filling rate are the main influencing factors. The amount of filling is fixed. In order to ensure sufficient impact force, the diameter of the sphere can be reduced and the number of spheres can be increased to increase the number of impacts on the mineral and improve the crushing efficiency.

To ensure sufficient time for the material to grind in the mill, the ball must have the ability to control the flow rate to ensure that the material is fully crushed.

The law of two-level ball allocation

The use of two spheres of different specifications for grading is called two-stage grading, but there is a requirement that the diameters of the two spheres differ greatly. Its main function is to improve the impact capacity and the number of impacts of the mill. In addition, the higher bulk density allows the material to be fully ground.

In the two-stage ball distribution rule, the large balls are mainly used to crush materials, and the small balls are mainly used to fill the gaps of the large balls to increase the bulk density of the balls, thereby controlling the flow rate of the flow, thereby increasing the grinding The second is the transfer of energy; the last is to squeeze the coarse-grained materials in the gap into the impact area of ​​the big ball.

See details：https://www.pizzerie-u-pepy.cz

What to do if the flotation effect is not good?

 In the flotation process, there are many processes that affect the flotation effect. There are not only non-adjustable factors of ore properties, but also adjustable factors such as pulp concentration, pulp temperature, pH, flotation time, grinding fineness, and reagents. Let's introduce them one by one below.

Ore properties refer to the chemical composition, mineral composition, structure, structure and element occurrence state of the ore. The oxidation degree of the ore has a great influence on the flotation effect, because oxidation will change the original mineral structure and make the mineral composition It is more complicated, thus changing the physical and chemical properties, and at the same time, oxidation will change the pH of the pulp, which will affect the use of chemicals.

There is a great relationship between pulp concentration and recovery rate. Generally speaking, there is a normal distribution between the slurry concentration and the recovery rate. Only when the optimal concentration is reached, the recovery rate also reaches its peak. In the flotation process, the slurry must maintain a certain concentration of reagent to obtain good results. When the slurry is thicker, the reagent concentration should be increased accordingly. When the slurry concentration increases, the flotation time and processing capacity of the flotation machine should also increase accordingly.

The temperature of the slurry is also an important factor affecting the flotation effect. Heating can accelerate the movement of molecules, accelerate the dispersion and hydrolysis of the reagent, and increase the interaction speed between the reagent and the mineral surface.

The pH of the pulp often affects the floatability of the mineral, but the critical pH will change with the change of flotation conditions. Under certain conditions, any mineral has a suitable pH value, and only under this value can a better flotation index be obtained.

Flotation time refers to the residence time of the slurry in the flotation tank. To determine the best flotation time, it should be determined in advance through the beneficiation test. When the floatability is good, the content of the minerals to be floated is low, the slurry concentration is small, the agent has a strong effect, and the flotation time is short. On the contrary, longer floating time is required.

The appropriate grinding fineness should be determined according to the particle size of the useful minerals, to dissociate the useful minerals from the gangue, and minimize the symbiosis between the minerals and the gangue. For single minerals, the fineness of grinding must be less than the upper limit of the floating particle size of the mineral.

However, it should be noted that the finely ground particle size of the ore will also have an adverse effect on the flotation effect, so the selection of the appropriate grinding particle size is of decisive significance for the final effect.

In the flotation process, the agent addition system is called the formula, which mainly refers to the type, quantity, order, addition point and preparation method of the agent. The type of medicament is mainly determined by the results of ore selectivity research, and the dosage of medicament is determined by the beneficiation test and practical experience. In the actual operation process, timely adjustments should be made according to changes in the situation. It is determined according to the dissolution rate and action time of the drug.

Every detail in the flotation process will affect the final flotation effect. It is recommended to conduct a beneficiation test before flotation, and determine the process parameters according to the beneficiation test results to achieve the best results.

How to determine the reasonable load of the grinding body of the ball mill

 The configuration of the grinding body of the ball mill will have a great influence on the output quality of the ball mill. If there is a gradation of the grinding body, then the conditions such as the load of the grinding body must be fully considered. The following briefly introduces the calculation method of the grinding body.

The first condition is the filling rate of the abrasive body. So what is the filling rate of the abrasive body? The percentage of the filling volume of the grinding body compared to the effective volume is called the filling rate of the grinding body. Generally speaking, if the filling rate of the grinding body is too high or too low, the grinding efficiency of the mill will be too low. For the grinding body filling rate greater than 32%, you can use the formula to calculate:

Φ0=113-126H/Di

Since there are many influencing factors of the grinding body, it is necessary to find a better filling rate in the production and adjust the equilibrium state according to the degree of change of the influencing factors.

Then we have to mention the loading capacity of the grinding body. What is the loading capacity of the grinding body? It is the quality of the grinding body loaded into the mill (or in the container), and the size of the load mainly depends on the filling rate of the mill. The calculation formula of the loading capacity of the grinding body:

G=VΦ0

                                                G=0.00785Di2LΦ0

It can be seen from the above that G——loading capacity (t), V——effective volume (m3), Di——effective diameter (m), L——effective length (m), Φ——filling rate (%), P ——Bulk density (t/m3)

How to choose economical and reasonable mining methods for different mines?

 Mining method is the core of mining. It can be said that the choice of mining method determines the operation of the entire mining system. The selection of a correct and reasonable method of mining for a mine plays a decisive role in the future production and operation of the mine. Inferiority determines the mining efficiency, production scale, ore recovery rate, and ore quality of the mine. The method of mining is restricted by many factors, such as the geographical location of the ore body, the stability of the ore rock, the type of ore, the taste of the ore, and the depth of burial.

Although the burial elements of mineral deposits vary widely, in general, some rules can be summarized for the selection of mining methods, which are mainly divided into the following four situations:

1. If the buried depth of the ore body is shallow, and the extension depth is also shallow, all deposits are mined in open pit.

2. If the buried depth of the ore body is very deep, underground mining is adopted for all deposits.

3. If the burial depth of the upper part of the ore body is shallow, and the extension depth is very deep, the upper part of the ore bed adopts open-pit mining and the lower part adopts underground mining. In this case, in the middle of production, a transition period from open-pit mining to underground mining is needed.

4. The upper part of the ore body has a deeper buried depth, and the extension depth is shallower, all of which may be open-pit mining or all underground mining.

Failure analysis of ZGMn13 liner of ball mill

 Through the macro inspection and the onlooker inspection, it can be found that the liner of the ball mill will occasionally show loose casting, oxides, and a large number of massive unmelted carbides and needle-like carbides.

    The ideal microstructure of high manganese molten steel after treatment is a single austenite, but due to the metallographic examination of the liner, there are a large number of unmelted massive carbides and precipitated needle-like carbides in the microstructure. This is because the heating temperature is too low during the water toughening treatment, or the holding time is too short, so that the carbides are not fully integrated into the austenite. In the subsequent quenching and cooling process, a large amount of precipitation may be due to insufficient cooling speed. Needle carbide. From the field investigation, the heating temperature of the heat treatment furnace will be lower than the temperature required by the process due to long-term neglect and maintenance; when the water toughening treatment is cooled, because the water tank is too small, the treated tonnage is too heavy. The water temperature after cooling cannot be kept below 60 degrees Celsius, which reduces the cooling rate; if the workpiece stays in the water for too long from the furnace to the water, these will make the microstructure after the water toughening treatment appear abnormal.

    The chipping of the liner of the ball mill is mainly due to the improper longevity of the heat treatment process, the defective structure and casting shrinkage, as well as the existence of coarse non-metallic debris, which reduces the strength and toughness of the liner. Under the action of this, it will lead to the early failure of the liner.

Specific details can be consulted：https://clactononseaessex.uk/

Movement form of hydrocyclone fluid

The hydrocyclone is a separation device that uses the principle of centrifugal sedimentation to separate or concentrate the slurry. Because of its simple structure, large workload, high separation efficiency, low cost, and low maintenance cost, it has been widely used in mineral processing, petroleum and chemical industries. The structure and size of the hydrocyclone are very important for separation. The diameter and underflow of the hydrocyclone are very important parameters that affect the working capacity and separation efficiency. For a larger cyclone diameter, the separation efficiency is low, but the working capacity is high. Therefore, if the separation efficiency of the large-diameter separator is satisfied, it is preferred. For solid-liquid hydrocyclones, increasing the underflow will increase the flow rate of the underflow. However, if the amount of underflow is too large, a large amount of water will flow out from the outlet of the underflow pipe, thus impairing the function of the underflow pipe. On the contrary, if the underflow diameter is too small, it may block solid particles, especially when the feed slurry is disturbed by a large concentration. Therefore, designing a proper hydrocyclone diameter and underflow pipe size is the key to improving the separation efficiency of the hydrocyclone.

                            

The structure of the hydrocyclone looks very simple, but the requirements for its structure, productivity, and grading effect are very high, and high matching degree can improve efficiency and productivity. Structural factors directly affect the flow form and movement mode of the fluid inside the cyclone. The fluid movement in the hydrocyclone mainly has the following forms: internal and external swirling flow, under-cover flow, balanced flow, and zero-speed envelope surface. The direction of rotation of the inner and outer swirling flow is the same, both clockwise or counterclockwise, but the direction of rotation of the swirling flow is opposite, the outer swirling flow is from top to bottom, and the inner swirling flow is from bottom to top. The underflow of the cover is also called short-circuit flow. It is due to the centrifugal force and the frictional force of the inner wall of the cylinder, a small part is suddenly released under the influence of the nozzle and pressure, first hits the top cover and then moves downward, and finally overflows with the overflow. The flow port is discharged, because this part of the slurry is directly mixed into the overflow without separation, so it directly affects the separation effect. The balance flow is two streams of two-phase fluid rotating inside and outside. Due to the different sizes of overflow ports and different insertion depths, there is no time for the slurry to be discharged from the upper and lower discharge ports, and the part of the slurry fluid that is not discharged is overflowing Between the tube and the cylinder, there is a balanced vortex movement up and down to form a balanced vortex. But this part of the exercise generally does not affect efficiency. The zero-speed envelope surface is due to the different movement directions of the inner and outer swirling flows. The inner swirling flow is formed by the movement of the outer swirling flow. Relatively speaking, there is a separation surface, that is, there is a fluid separation track with an axial velocity approaching zero. surface.