General Properties of Loose and Granular Media

The physical properties of loose and granular media are important, both from the standpoint of the operation of the filtration device, but also from the standpoints of feeding and storing these materials in bins and silos. These considerations are equally important and quite pertinent to dry chemicals that are used as filtration aids (Chapter 3). In a general sense, loose solid matter is comprised of large numbers 

The ratio of p JPmin be as high as 1.52 depending on the material. Consequently, when bulk densities are reported it is important to note whether the value was determined under loose or tapped conditions, along with the mean particle size. Most literature values report an average bulk density that is representative of the material most often handled. Loose solids may be broadly characterized according to their bulk densities  

loose solids have no forces of attraction between  

Bulk density is related to particle density through the interparticle void fraction e in the sample. 

The value of e varies between the limits of 0 and unity however, many particles have a loosely poured voidage of approximately 0.4 to 0.45. 

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