Hemlock sawdust

Hemlock sawdust was ground past a 0.8 mm. screen in a laboratory mill, and then subjected to five different levels of irradiation using a Gammacell 220 (Atomic Energy of Canada Limited, Ottawa) as the source of gamma irradiation. The irradiation dosages ranged from 4.85 X 106 to 1.46 X 108 rads. 

Figure 1. The effect of gamma irradiation of hemlock sawdust on certain of its chemical constituents and on its susceptibility to rumen microbial action in vitro. ADF = acid-detergent fiber ADL = acid-detergent lignin CD = cellulose digestion DMD = dry matter disappearance...

The amount of reducing sugars formed from alder sawdust by the activity of CFE of rumen microorganisms increase with increasing levels of gamma irradiation up to a dosage of 1.46 X 108 rads. (Table X). The results parallel very closely those obtained with in vitro fermentation tests on hemlock sawdust (Figure 1). 

Comparison of the oxidatively-heating property of the soot which arises from the incineration of the sawdust of Western hemlock and accumniates in the soot collector set up at the top of the incinerator, with, the oxidatively-heating property of the sawdust of Western hemlock... 

It is shown in Fig. 101 that the calorific value of the soot is far larger than that of the sawdust of Western hemlock. 

It is shown in Fig. 102 that the soot heats oxidatively about 4.4 times as fast as the sawdust of Western hemlock. That is, it has been proved that the soot is very inflammable. It thus follows that sufficient care should be taken to handle every soot. 

Figure 102. Comparison of Ihe oxidatively-heating curve, of the soot, which arises from the incineration of the sawdust of Western hemlock and accumulates in the soot collector set up at the top of the incinerator and is charged in the draft cell, into which air is supplied, and is subjected to the adiabatic oxidatively-heating test started from a near 150 C, recorded in temperature increments of 3 K from the corresponding standard temperature, with, the oxidatively-heating curve of the sawdust of Western hemlock placed under the same conditions as the former.

The availability of both the cellulose and hemicellulose in untreated wood sawdust is low and for conifers such as lodgepole pine, eastern hemlock, and balsam fir is essentially zero. 

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