64 BULLETIX 983, U. S. DEPARTMENT OF AGRICULTURE. 
a long. open, covered shed with an inclined bottom sloping into a 
trough, similar to those used for the storage of sugar beets, would 
answer the purpose; or the material may be windrowed in piles and 
permitted to hopper itself, the danger of its rotting in the hoppers 
being obviated by this plan. 
All hoppers, both in the storage building and over the digesters, 
as well as all other parts of these buildings coming in contact with 
the hogged and shredded waste, should be either of steel or of heavily 
creosoted timber construction in order that decay may be avoided. 
The green shredded wood makes an ideal medium for the cultiva- 
tion of wood-destroying fungi, and even in exposed places too dry^ 
it would seem, for decay to take place, the writer has found it pro- 
gressing rapidly wherever there were accumulations of fine stuff. 
DISINTEGRATING EQUIPMENT. 
The disintegrating equipment should consist of hogs or chippers, 
shredders, and screens. A chip one-half an inch long in the direction 
of the grain will be penetrated thoroughly with acid, but the ease 
with which the sugar can be leached out is a problem that requires 
attention. However, as the residual digested sawdust or waste after 
extraction is ample for power production, and as all exhaust steam 
from the engine has value for heating and distillation purposes, the 
extra power required to chip down to a three-sixteenths or one- 
quarter inch chip would not be prohibitive, and the greater efficiency 
of extraction would probably make the chipping down very desirable. 
After being screened — for the screenings should be reshredded — the 
fine stuff should go bv belt to the loading bin over the digester. 
SAWDUST AND ACID STORAGE. 
The loading bins should be of sufficient size to serve as intermediate 
storage for the material as it comes from the screen on its wav to the 
digester. Each of the bins should hold several digesterfuls and 
should be placed over the digester, being tapered down so that the 
material may flow directly into the digester, according to the arrange- 
ment in chemical-pulp plants. 
The acid intended for the plant should be in concentrated form, 
to permit of shipment in tank cars and storage in steel tanks. The 
concentrated acid should be pumped into a lead-lined tank above the 
digester and be diluted in order that the dilute acid may flow into 
the digester along with the sawdust. If rotating digesters are used, 
no special mixing apparatus will be necessary; at least, no appre- • 
ciable quantities of uncooked material have ever been found at the 
Forest Products Laboratory when such digesters were used. 
