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