During the Eighties Sider began to be interested in the study of the moulding process with sand/silicate and to the consequent regeneration of sand. In 1987 it realized the first plant for the reclamation of sand bonded with sodium silicate.
The continuous development of the technology in the following years has carried today Sider Technology to plan and construct systems allowing to reclaim till more than 90% of the used sand.
The sand reclaiming process is subdivided in more steps:
The vibrating shakeout equipment crushes the sand blocks, in order to turn them to grains or to very small size. Metallic parts, stones or other foreign matters are kept by a screening surface and are discharged through a pneumatically opened shutter
Sand coming from the shakeout is conveyed upwards through suction. During such transport it undergoes, because of the speed, a crushing and a rubbing of the grains
In the decantation chambers, a first separation and elimination of dust is carried out
The dusted and treated sand is screened, leaving to pass the definitively selected one to the successive phase
Through the hot-air fluid bed, the grains are heated and dried, in order to favour the shattering of the silicate film covering them. Afterwards the rubbing of the grains pulverizes the silicate film, while dust is removed and stored in the hopper of the proper sleeves filter
The sand is cooled uniformly in a heat exchanger with finned tubes batteries before its definitive ensilage
A pneumatic propulsor, placed under the cooling-unit, conveys sand to the usage point
In order to improve the quality and to optimize the silicate consumptions, sand is treated for a last time in a final dust exhausting group provided with an adjustable cascade system. In such way also the residual fines together with dust produced during the pneumatic conveyance are captured, and you obtain a sand with eccellent granulometry features