This is just one of the many applications/uses for the Merlin-VSI™ range of crushers. With worldwide stockpiles of waste glass forever growing and government taxes on landfill becoming ever more expensive, Sandvik Rock Processing’s autogenous crusher Merlin-VSI provides a cost effective solution to the problem. This type of crusher uses glass to crush glass, resulting in an extremely cost effective, clean, contaminant free product with no sharp edges. In fact it looks and resembles the sand found on the best holiday beaches around the world.
Case Study – Visy Recycling
In June 2004, Sandvik Rock Processing set up a glass re-cycling plant in Sydney Australia in co-operation with Visy Recycling, Australia’s leading recycling company. The purpose of the plant was to prove the concept of recycling container glass, instead of dumping to waste landfill sites as is currently the case.
Scope and Success of the Project
Sandvik Rock Processing personnel worked closely with Visy to install and arrange a crushing and screening circuit that would handle up to 50 tonnes per hour of glass.
Within a week of the trials, it was evident that the process was destined to be a huge success.
Visy are now considering establishing further such facilities in Australia.
Uses of Recycles Container Glass
In the process metal bottle tops are separated into a waste bin, then paper, plastic tops etc. are further removed and collected in separate bins. The glass is then separated into varying fraction sizes, 0-250µm, 250 - 800µm, 800µm - 1.2mm and 1.2mm – 3mm. The minus 250µm is used mainly for recycling into new glass products by the glass manufacturers. The fraction sizes above 250µm are currently being used for blending with natural sand for concrete production.
However this is not the only use for re-cycled glass. Other uses include bunker sand for golf courses, sand for children’s play areas, as a filter medium in aquariums, as an attractive finish for patio slabs and many more.
How Does Merlin-VSI Work?
The unique crushing and grinding action of the Merlin-VSI range of crushers, makes it ideally suited in the recycling of glass. Bottles and jars are firstly broken roughly, either by a shredder, jaw crusher or similar, to produce a -50mm feed for the Merlin-VSI. This material enters the Feed Hopper of the crusher and the process begins. The material flows through the Feed Hopper and enters the Hurricane™ rotor where centrifugal force accelerates the material along a “glass lined” shelf within the rotor itself. Here the grinding of the glass starts.
The glass is then ejected at around 60M/sec into the “glass lined” Crushing Chamber, where impact, attrition and grinding all take place simultaneously producing a “glass on glass” crushing action. This crushing action ensures that the wear costs (cost per tonne) are very low and that there is no contamination from the crusher wear parts. The Merlin-VSI crusher can consistently produce a -3mm crushed glass product which closely resembles “natural sand”. Particle shape is maintained throughout the product curve producing a crushed glass that has no sharp edges.