MECHANICAL RECLAMATION OF WASTE SAND PRODUCED BY ADDITIVE MANUFACTURING PROCESSES

Metal casting manufacturers are increasingly adopting three-dimensional printing in their workflows as a way to remain competitive. Despite all the innovative development, strict environmental regulations and the intrinsic value of sand still make the recycling of waste sand an essential matter to consider when implementing the rapid sand-casting process. During the printing of the furan-bonded sand cores using binder jetting processes, waste sand is produced. This paper investigates the possibility of mechanically reclaiming the waste sand generated during the printing of sand cores. In this study, waste furan-bonded sand that was generated by three-dimensional printing using the Voxeljet VX 1000 printer was collected from the Vaal University of Technology. The collected waste sand was first characterised before being mechanically reclaimed using dry attrition, followed by dry screening and wet attrition, which involved washing the waste sand in a liquid solution of water and isopropyl alcohol. The results showed that mechanical reclamation using wet attrition is more effective in removing the residual binder in the sand than mechanical reclamation using dry attrition.