PROCESS FOR PREPARING SOME LOW DENSITY POROUS COMPACTS FROM A FINELY MILLED SILICA MIXTURE, OPTIONALLY IRON AND COAL-BEARING REDUCING AGENT

摘要

The process for the preparation of low density porous compacts, from a fine crushed mixture of silica, optionally iron and carboniferous reducing agent, in the presence of a binder and possibly of a braking agent and in approximately stoichiometric quantities corresponding to the subsequent reduction to the respective silica. Ferrosilicon, according to the invention, eliminates the disadvantages mentioned above by using a finely coated material with silica content of 25 .... 100% by weight of silica powder, 0 .... 75% by weight of silica sand and 0. ..75% by weight silicon pebble, this material, possibly together with iron particles, mixes with the finely chopped carboniferous reducing agent such as oil coke and or coal with cereal binder such as wheat starch and about 50 parts. total silica weight, thus forming a wet mixture which is first deposited in a thin layer about 5 cm thick on a flat surface and then east it is dried at high temperatures above 200 degrees C for water removal, after which the dry layer is broken into pieces of different irregular shapes and sizes.