| 摘要 |
<p>Tar bonded refractory shapes consisting of dead burned basic refractory material are obtd. by: (a) hot-mixing (i) a batch of graded granular refractory material (e.g. dolomite, magnesite opt. with added lime), (ii) a carbonaceous binder (e.g. coal tar pitch, bitumen, tar, or crude oil derivative), together with (iii) an aromatic nitro cpd., or mixt of such cpds. that melts (but does not decompose) below mixing temp. in amt. of 10-30 wt. % of (ii); (b) pressing the batch into shapes, and (c) toughening the shapes by heating at 230-350 degrees C for several hours. Object is to provide tempered basic refractory shapes of considerably increased strength but with increased fixed carbon content. The shapes may be used in vessels for steel making by the Oxygen Process. Aromatic nitro cpds. suitable include m-dinitrobenzene and dinitrotoluene.</p> |
