The relationship between ball loading and output of ball millDate: 2019-07-09 Views:
Ball mill is one of the common equipment in mineral processing equipment. The reasonable ball loading quantity of ball mill not only affects the improvement of grinding efficiency and production theory, but also relates to the service life of ball mill.Therefore, it is very important to master the reasonable and balanced ball loading quantity of the ball mill.The following to introduce the ball mill load ball amount of the relevant issues.
1. Ball loading quantity and output of ball mill
The output of ball mill is directly related to the quantity of ball.When a ball mill works, its efficiency generally depends on the sum of the work done by each ball (the number of impacts and the impact force).Therefore, it is necessary to give full play to the effectiveness of each steel ball, which is required to move along a different trajectory (trajectory), as far as possible to avoid collision.Too many steel balls may pile up with each other, which may cause some of them to fall down when they are not raised to the required height, thus failing to give full play to the crushing capacity of each ball. At the same time, it increases the kinetic energy to eliminate.Too little. Although the crushing capacity of each steel ball is fully developed, the total crushing capacity is still limited.Therefore, an appropriate amount of ball loading must be selected.
According to the actual results of the laboratory, when the filling amount of steel balls in the cylinder is 40%, the output is the highest, and the filling rate of the general steel balls in production is about 35%, that is to say, the filling volume of the balls is lower than the horizontal center line.
2. What is the most suitable amount of ball loading in the ball mill?
When the speed of the ball mill is set, the volume of the ball is only 10% of the volume of the ball mill cylinder.The ball moves mainly in the form of sliding, and there is no running water in the ball.As the load gradually increased to 30 per cent, the motion of the ball, although still dominated by sliding, began to show the required inclination.When more than 40 per cent of the ball is filled, the ball's motion is dominant in the form of a dip;When the ball load reaches 50% of the total capacity of the cylinder, because the surface of the ball group is exactly on the diameter line of the cylinder, it is easy to produce dumping flow.Therefore, it is appropriate to load the ball between one third and one half, and one half is the most ideal.
3. How to check whether the ball loading amount of the ball mill is appropriate or not?
The so-called impact of ball loading should mainly consider the size and proportion of ball loading, as for the number of ball loading, has been basically fixed in production, such as the central row ore type ball mill, its ball volume to not make steel ball rolling out of the ball mill is limited, and the grid type ball mill ball volume should account for 50% of the total volume.During the test, the operating conditions of the ball mill, such as the grain size of the ore, the overflow fineness of the grader and the amount of sand returned should be kept unchanged as far as possible, and then the rationality of the ball-loading ratio can be checked from the following two aspects.
(1) the amount of ore and grading machine overflow fineness is unchanged, and the return of sand decreased, it shows that the grinding effect of the ball mill is strengthened, then can increase the amount of ore.
(2) According to the screening analysis results of sand return by the classifier, it is found that the number of ore particles close to the overflow size increases, indicating that the number of pellets is insufficient;On the other hand, an increase in coarse grains indicates a shortage of large spheres.