The dependence of the power demand of a mill on the nature of the pulp does not appear to have received a great deal of study, and, in general, observations on this matter take the form of general statements. For example, Taggart states that, other things being equal, wet milling requires 60-90 % of the power … Read more
The choice between wet and dry milling is, in general, unimportant in small-scale milling but is a major technical problem when large-scale milling in the metallurgical industries is involved. On purely mechanical grounds it is difficult to see any great difference in fundamental principles between wet and dry milling, since dry milling may be regarded … Read more
In an air-swept mill, the body of which does not differ significantly in general design from a trunnion overflow mill, a powerful stream of air is passed through the mill and removes the finer particles produced by the grinding process. This stream of powder-laden air is then passed through the classifier and the “oversize” material, … Read more
The power required to drive a tumbling mill is of interest both to the designer and to the mill operator: to the former as a basis of design for the determination of the necessary size of the elements of the machine; and to the latter because all other factors being equal, the most economical machine is … Read more
In all ore dressing and milling Operations, including flotation, cyanidation, gravity concentration, and amalgamation, the Working Principle is to crush and grind, often with rod mill or ball mill, the ore in order to liberate the minerals. In the chemical and process industries, grinding is an important step in preparing raw materials for subsequent treatment. … Read more
A mill consists of a steel shell supported at each end by a hollow trunnion running in a bearing, lined with steel plates, and driven by belt and gears or by motor and gears. The mill is set at a slight slope and is fed with finely crushed ore and water through one trunnion. When … Read more
The cost of replacement of the metal worn from the working surfaces of the balls and liners of a mill often represents a considerable fraction of the cost of operation of the plant and so is of some real economical importance. In spite of this importance, however, the amount of information in available on this subject … Read more
In the previous chapter, the various “laws” of comminution which have been propounded have been studied in relation to the physical process of size reduction and to the available results of experiments into the fracture of homogeneous and heterogeneous materials by impact and by slow compression. In this study it is seen that no satisfactory … Read more
The problems associated with comminution of solid bodies in numerous and complex. In spite of the large amount of investigation which has been undertaken, the present state of knowledge is such that there is no theory by means of which the behaviour during fracture of even a single particle under the simplest possible mode of loading can … Read more
