Lime-granulate high strength bricks for thermal insulation - prepd. by crushing blast furnace slag or other slag, mixing with lime then moulding

摘要

Lime-granulate bricks are made using the sand-lime brick mfg. process, and a slag granulate crushed in a roller-crusher. The slag is obtd. esp. from blast furnaces; boilers; burning rubbish; or in the direct mfr. of steel. After crushing, the slag contains 15-50% fine grains 0.2 mm size, and is used with 1-6% (w.r.t. total wt.) of lime calculated as CaO. When using blast furnace slag contg. 40% CaO, the crushed slag pref. contains 16-20% fines 0.2 mm and 3-4% CaO is used. The crushed slag pref. has max. size 2 mm, obtd. by crushing twice in a pendulum mill. The mixt. of slag and lime may also contain 1-2% cement; and if the slag has a wt. 1.2-1.5 kg/l, up to 10 wt.% of natural sand may be added to the slag. Used for mfr. of bricks with improved compression strength and thermal insulation compared with conventional materials.