| 摘要 |
Carbon black is uniformly wetted with 1/2 to about 1 1/2 times its dry weight of water to produce a loamy mass of such consistency that it will not flow under its own weight but will cohere when pressed, then subjected to shearing forces under pressure, e.g. by mixing in a dough mixer, milling, extruding, or forcing through a fine mesh screen or meat grinder, of such duration that the compressibility (the percentage reduction in height of a sample of pellets when subjected to 125 lbs. per sq. inch pressure) of the dried pellets produced is less than 30-35 per cent, and finally pelleted by known methods such as by agitation or impact action of the type described in U.S.A. Reissue Specification 21,379. The carbon black may be predensed and the ratio of water to carbon black is usually adjusted by addition or evaporation to 1:1, after the preliminary treatment, for efficient pelleting. The finished pellets may be oven dried. |
