There is little information available about the re-use of abrasive grits. Especially for the expensive superabrasives, recycling is important under the growing awareness of material and energy efficiency. McClarence [MCCL10b] estimated in 2010 that only between 8-10 % of new diamond is reclaimed.
4.8.3.1 Conventional Tools
Conventional grinding wheels can be crushed and backfilled in roadworks. Re-use of the abrasive layer is difficult, because inhomogeneous density and heterogenous particles with variable diameter decrease tool toughness and increase the danger of cracks and tool breakage in vitrified bonded tools [BEHR11b]. Because of high safety and liability requirements for rotating abrasive tools, grinding wheel manufacturers have refrained from using recycled raw materials [BEHR11b]. There are also some attempts to regain abrasives from conventional grinding wheels for refractories, but this is a down-cycling of abrasives.
Recently, a new manufacturing procedure for vitrified bonded tools from partly recycled tool material was invented [BEHR11b]. The tools consist of an abrasive layer made from new materials and a body material made with recycled materials in the form of particles with a minimum diameter of two times the grit diameter.