| 摘要 |
<p>1,203,037. Porous concrete aggregates. ROTAG DEVELOPMENT CO. Ltd. 14 Nov., 1967 [29 Nov., 1966], No. 53412/66. Heading ClH. Concrete aggregates are obtained by mixing water with clay-free pulverized fuel ash, pelletizing and passing the pellets from the hot to the cool end of a rotary kiln to fire them. Steam formed from the water expands the pellets. Optionals are surfactants (amount given, but no examples), organic resin dispersion or sawdust which burn away leaving voids.</p> |
