Hemp Hurds as Paper-Making Material - United States Department of Agriculture, Bulletin No. 404 by Lyster Hoxie Dewey;Jason L. Merrill
page 5 of 40 (12%)
page 5 of 40 (12%)
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may constitute all objectionable feature in the use of hemp hurds for
paper stock. In Italy and in most localities in Russia and Austria-Hungary where hemp is extensively cultivated, it is retted in water, but water retting has never been practiced in the United States except to a limited extent before the middle of the last century. Hurds from water-retted hemp are cleaner and softer than those from dew-retted hemp. The fiber is sometimes broken from dry hemp stalks without retting. The hurds thus produced contain a small percentage of soluble gums, chiefly of the pectose series. Comparatively little hemp is prepared in this manner in America. Process retting by means of weak solutions of chemicals or oils in hot water is practiced to a limited extent. The hurds from these processes may contain traces of the chemicals or oils and also soluble gums in greater degree than those of the dew-retted or water-retted hemp. =PROPORTION OF HURDS TO FIBER AND YIELD PER ACRE.= [Illustration: FIG. 1.--Hemp-breaking machine. The stalks are fed sidewise in a continuous layer 2 to 3 inches thick, turning out about 4,000 pounds of clean fiber per day and five times as much hurds.] The yield of hemp fiber varies from 400 to 2,500 pounds per acre, averaging 1,000 pounds under favorable conditions. The weight of hurds is about five times that of the fiber, or somewhat greater from hemp grown on peaty soils. A yield of 2-1/2 tons of hurds per acre may be taken |
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