The results of investigations of thermal reclamation of spent moulding sands originating from an aluminum alloy foundry plant are

presented in this paper. Spent sands were crushed by using two methods. Mechanical fragmentation of spent sand chunks was realized in

the vibratory reclaimer REGMAS. The crushing process in the mechanical device was performed either with or without additional

crushing-grinding elements. The reclaimed material obtained in this way was subjected to thermal reclamations at two different

temperatures. It was found that a significant binder gathering on grain surfaces favors its spontaneous burning, even in the case when

a temperature lower than required for the efficient thermal reclamation of furan binders is applied in the thermal reclaimer. The burning

process, initiated by gas burners in the reclaimer chamber, generates favorable conditions for self-burning (at a determined amount of

organic binders on grain surfaces). This process is spontaneously sustained and decreases the demand for gas. However, due to the

significant amount of binder, this process is longer than in the case of reclaiming moulding sand prepared with fresh components.

The results of investigations of spent moulding sands taken from the mould at various distances from the surface of the produced casting,

are presented in the paper. The casting mould was made with an application of the cooling system of the metal core in order to increase the

cooling rate of the ladle casting. As temperature measurements in the mould indicated the heat flow from the metal did not create

conditions for the complete burning of a moulding sand. The analysis was performed to find out changes of spent moulding sands caused

by degradation and destruction processes of organic binders. Conditions occurring in the casting mould were discussed on the bases of

testing: ignition losses, dusts contents, pH reactions and the surface morphology of the moulding sand samples. Factors limiting the

effective mould degassing were pointed out. Operations, possible for realization, which can limit the reasons of a periodical occurrence of

increased amounts of casting defects due to changing gas evolution rates being the result of the technological process, were also indicated.