Crushing of Mineral Particles by Control of Their Kinetic Energy

The present paper studies the energy size relationshipof minerals using a specially designed centrifugal crusher withrotation frequency control. The feed particles are accelerated bythe rotating disc of the crusher and they crush on the oppositevertical wall having the predetermined specific kinetic energy.The mathematical modelling shows that the specific energy,energy per unit mass of the particles, is independent of their massand is calculated to depend on the rotation frequency and thedisc diameter. Crystalline limestone, marly limestone andserpentine samples are tested. The results obtained are used topresent the energy–size relationship and to compare the crushingamenability of the rocks tested. A suggestion for further study isto derive the mathematical model of the breakage curves and tocalculate the breakage energy for each size class using the modelto be proposed

Crushing of Mineral Particles by Control of Their Kinetic Energy

The present paper studies the energy size relationship of minerals using a specially designed centrifugal crusher with rotation frequency control. The feed particles are accelerated by the rotating disc of the crusher and they crush on the opposite vertical wall having the predetermined specific kinetic energy. The mathematical modelling shows that the specific energy, energy per unit mass of the particles, is independent of their mass and is calculated to depend on the rotation frequency and the disc diameter. Crystalline limestone, marly limestone and serpentine samples are tested. The results obtained are used to present the energy–size relationship and to compare the crushing amenability of the rocks tested. A suggestion for further study is to derive the mathematical model of the breakage curves and to calculate the breakage energy for each size class using the model to be proposed

Removal of Phenols from the Water Effluents of Olive Presses

The water effluents of olive presses contain a number of phenols that are hardly biodegradable and therefore constitute an environmental hazard, mainly in the Mediterranean countries. The present work presents the results obtained from the study of artificial solutions containing one kind of phenol, namely gallic acid that consists of the main type of phenols present. According to the experimental procedure, the phenol is removed from the water solution by absorption on different naturally occurring raw rock materials. The first material is caustic magnesia produced after the calcination of a magnesite sample from Macedonia, Greece, the second is a sample of sedimentary psammitic marl from the area of Chania, Crete, Greece, and the third solid absorbent is a bentonite sample from the island of Milos, Greece. According to the results obtained, magnesia seems to be by far the best absorbent, with an absorbing capacity of 3500 mg of phenol per gram, followed by the psammitic marl. The absorbing capacity of bentonite is almost negligible