Grinding

Mixer Mill – High Energy Ball Mill

A Superior Mixer Mill engineered for rapid and reproducible sample preparation procedures. This High Energy Ball Mill can handle simultaneously two or more samples from 0.2 ml up to 160 ml. Grinding, Mixing and Cell disruption in on machine. This MIXER MILL is designed for “1001 laboratory applications”. Typically Processing times are between 15 and 45 … Read more

Add Steel to Convert AG Autogenous Mill SAG Mill

Metallurgical evaluation of autogenous grinding of Anaconda’s Berkeley Pit ores indicated that tonnage throughput increases, at a finer flotation feed size, were possible by converting autogenous mills to steel ball mills. In addition, initial test work showed that the improved grind resulted in slight recovery gains in subsequent flotation processing. Operation of the Autogenous Mills … Read more

Size Reduction Mineral Liberation Model

Success has been achieved in developing mathematical models of rod mills, ball mills and recently to a limited extent autogenous grinding mills. There is also considerable activity in the development of mathematical models of various mineral concentration operations, such as flotation, magnetic separation and electrostatic concentration. However, at present there is a technological gap which hinders … Read more

Predicting Particle Size Distributions in Open & Closed Circuit Mills

A size-continuous breakage kinetics model is postulated and supported with industrial grinding mill data. It is shown that the kinetics parameters include the effects of possible classification at the mill discharge. The estimated parameters were then used in the kinetics model to simulate the behavior of a grinding mill in open and closed circuit operation. … Read more

How to Use Ore Grindability to Evaluate Plant Performance

A number of methods to simulate the Bond work-index parameter are used and several of these methods have been reported in the literature. Smith and Lee used batch-type grindability tests to arrive at the work index. They made comparisons, at various grind sizes, with work index values using the standard Bond grindability tests. Another method … Read more

Pinto Valley Concentrator Grinding with Large Diameter Ball Mills

The Cities Service Company’s Pinto Valley mine and concentrator lie about 6 miles west of the town of Miami, Arizona at an elevation of approximately 4,000 feet above sea level. The concentrator started its first ball mill in July 74 and all six were available by November. Every effort was made to reduce capital costs, … Read more

How to Control a Grinding and Classification Circuit

The system chosen has a “fill in the blanks” process control compiler that permits the control loops to be constructed at the system teletype in the conversational mode. The control loops are constructed by linking together various computational and control blocks (which are control algorithms) to achieve the desired control. There are twenty odd blocks … Read more

Control Wet Grinding Circuits

Ideally, mill circuits should be controlled so that excessive random disturbances are reduced in frequency and amplitude. It is difficult to derive an objective measure of the effectiveness of any chosen control strategy. Often, the response of the circuit to pulse or sinusoidal disturbances is used as a measure of the effectiveness of control. Linear … Read more

Semi-Autogenous Grinding of Copper Ores

Mechanism of Size Reduction The spectrum of comminution mechanisms in a mill range from shattering of the rock by imposition of a load to abrasion by surface contact with other rocks. Since SAG represents a combination of autogenous and ball milling, a better understanding of the mechanism of the comminution process in a SAG mill … Read more

Factors having an Effect on the Power Consumption & Capacity of a Mill

Since man began beneficiating ores, a limited number of factors influenced the type of treatment. The ore itself has always been a factor. The first form of concentration was probably hand sorting, and the grade of concentrate and recovery had to be considered from the start. Five of the principal factors having an effect on … Read more