Grit content

Federal Test Method Std. 175B, Method 4041.1 Grit, lumps, or undissolved matter in adhesives. 

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The grit content of coarse mica is deterrnined by the vanning method. A 25-g sample of dry mica is placed on a vanning plaque or a 21.6 x 28-cm... 

There arc several conventional tests required hy consumers of ground mica. They include screening and Ihe determination of bulk density, true specific gravity, chemical analysis, moisture, free silica, refraction index, oil absorption, brightness, grit content, and aspect ratio. 

Grinder Variables. The quaUty of pulp depends on wood species, moisture content, and grinder variables such as peripheral stone speed, grit size and number per unit area, and pattern on the stone surface. Process variables that affect pulp quaUty include grinding pressure pit consistency, ie, consistency in the space immediately below the grinder (2—6%) and temperature (40—80°C). The combination of moisture and raised temperature tends to soften the lignin. 

Finally, other properties of asbestos fibers may be evaluated depending on the envisaged appHcation. Typically, the grits and spicule content, the magnetic susceptibiUty (magnetic rating), the content in soluble chlorides, and the humidity level may be of a particular interest in specific appHcations. 

The CaO content of commercially available quicklime can vary quite widely over an approximate range of 70 percent to 96 percent. Content below 88 percent is generally considered below standard in the municipal use field. Purchase contracts are often based on 90 percent CaO content with provisions for payment of a bonus for each 1 percent over and a penalty for each 1 percent under the standard. A CaO content less than 75 percent probably should be rejected because of excessive grit and difficulties in slaking. 

The Terrazyme technology is intended for use on wastes such as bio sludges, industrial sludges, grease trap wastes, grit trap wastes, and other wastes with high liquid contents that must otherwise be solidified prior to landfilling. 

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