When {HEAD ~ the grain size} of the granulated blast furnace slag is less than {TAIL ~ 20 μm}, the density of the fixing carrier becomes too excessive at the time of baking so that the fixing carrier impairs its adherability for the activated sludge 
is less than
When { HEAD ~ the grain size } of the granulated blast furnace slag is less than { TAIL ~ 20 μm } , the density of the fixing carrier becomes too excessive at the time of baking so that the fixing carrier impairs its adherability for the activated sludge
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH