| 摘要 |
<p>2069749 9108068 PCTABS00005 The method permits recovery of spent foundry sand for reuse by eliminating, by combustion, the organic carbon substances with which the spent sand is impregnated; spent sand, after grinding to a uniform grain size, is placed into a cylindrical container (2) inclined with respect to the vertical and rotated slowly (4-6 revolutions per minute); then, a stream of oxygen is blown into the base of the receptacle through a distributor (5) which uniformly distributes it into the spent sand mass (20), and local combustion is initiated on the surface of the sand mass, at the top of receptacle, by means of a burner (31); finally the burner is extinguished whilst the delivery of the oxygen stream is maintained and the combustion proceeds and feeds itself by the effect of a progressive descent of the flame front (30) towards the base of the receptacle until complete destruction of the organic and carbon substances contained in the sand has taken place.</p> |
