Abstract
The method of the ongoing assessment of the reclaim quality originating from the mechanical reclamation is described in this paper. In the process, the triboelectric system of measuring amounts of dust in the dedusting part of a reclamation device was applied. Based on the online measurements of the amounts of dust generated in the spent sand-reclamation process and the post-process determinations of the ignition losses and granular structures of the removed dust, the proper work parameters of the experimental reclaimer were selected. The allowable value of the ignition losses as well as the main fraction of the reclaimed matrix being similar to fresh sand was assumed as the main criteria of the positive assessment of the process. Within the presented investigations, a periodically operating device for rotor-mechanical reclamation was developed. The possibility of changing the intensity and time of the reclamation treatment as well as the triboelectric system of the dust-amount measuring were applied in this device. Tests were performed for the spent moulding sand with phenol-resol resin Carbophen 5692 hardened by CO2. This sand represents the moulding sand group with a less harmful influence on the surroundings for which the recovery of the quartz matrix utilising the reclamation requires stricter control of the parameters of the reclamation process and reclaim quality.
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