Crushing and grinding

Crushing and grinding uses mechanical force to break larger particles into smaller ones. A variety of tools are used depending on the particle s size and hardness. Large particles are crushed using jaw crushers capable of reducing particles to diameters of a few millimeters. Ball mills, disk mills, and mortars and pestles are used to further reduce particle size. 

A. J. Lynch, ed.. Mineral Crushing and Grinding Circuits, Elsevier, Amsterdam, the Nethedands, 1977. 

C. L. Prasher, Crushing and Grinding Process Handbook, John Wiey Sons, Ltd., Chichester, U.K., 1987. 

G. C. Lowrison, Crushing and Grinding Chemical Rubber Co., Boca Raton, Fla., 1974. 

The work index may be round experimentally from laboratoiy crushing and grinding tests or from commercial miU operations. Some rules of thumb for extrapolating the work index to conditions different from those measured are that for dry grinding the index must be increased by a factor of 1.34 over that measured in wet grinding for open-circuit operations another factor of 1.34 is required over that measured in closed circuit if the product size Xp is extrapolated below 70 [Lm, an additional correction factor is (10.3 + Xp)/l.l45X . Also for a jaw or gyratory crusher the work index may be estimated from... 

Dusts are solid particles generated by such processes as handling, crushing, and grinding. 

Bond, F.C., 1961. Crushing and Grinding Calculations. Part I, British Chemical Engineering, 6(6), 378-385 Part II, ibid. 6(8), 543-548. 

Vitreosil filtering, 103 see also Platinum apparatus Crushing and grinding 155 Crystal violet indicator, 308 Cupferron 170, 440, 471, 474 Cupron 442, 473 Current adsorption, 616 catalytic, 616 condenser, 595 diffusion, 592, 596 efficiency, 504 kinetic, 616... 

Salts pH of hydrolysed solutions of, 431 Samples crushing and grinding of, 155 dissolution of, 110, 801 weighing of, 76, 110 see also Analysed samples Sampling 150 errors in, 153 hazards of, 155 of gases, 153 of liquids, 153 of solids, 153... 

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