Tomra Sorting introduces Autosort Color for glass separation from MSW
New technology recovers more than 80 % of glass for recycling at purity rates of over 95%...
TOMRA Sorting Recycling has introduced AUTOSORT COLOR, a new unit which works in combination with AUTOSORT LASER to separate glass from municipal solid waste (MSW) with unprecedented effectiveness. AUTOSORT COLOR achieves purity rates of greater than 95% at high throughput rates, even when input materials are wet, dusty or dirty. Click here to see an animation of AUTOSORT Color in action.
Although many countries collect glass waste separately, a significant amount of recoverable glass still remains mixed in with MSW from households and businesses. Across Europe, glass content in MSW typically varies from 3.5% to as much as 9.8. Research by FEVE (the European Container Glass Federation) has revealed that the recovery of glass from MSW for recycling varies considerably from nation to nation. For example, Sweden, Norway, Switzerland and Luxembourg all achieve recovery rates of 95% or higher, but across much of Western Europe the rate is typically only 68% to 75% and five eastern European nations recycle less than 40%.
AUTOSORT COLOR enables sorting operations to extract this glass from the MSW stream for resale. It also reduces the risk of disruption, downtime and repair costs arising from damage to components when glass ends up in sorting machines that are not intended for glass.
Household waste that contains glass incurs higher incineration costs, so extracting more glass from MSW makes sense financially. Landfill costs will also be reduced by recovering glass from MSW.
Valerio Sama, Vice President and Head of Product Management Recycling at TOMRA Sorting Recycling, comments: “Globally, there is significant room for improvement in the recovery of glass from household and business waste. Separating more glass for recycling is not only better for the environment, but also makes better sense commercially, and with AUTOSORT COLOR both of those benefits are now achievable.”
Two-machine process recovers more than 80% of glass, with 95 purity
When developing AUTOSORT COLOR, TOMRA set out to recover a minimum of 80% of glass from MSW, with at least 95% of the recovered glass to be of a saleable quality. These targets were consistently met over many months at four facilities in Germany and Spain, including one which separates up to 3,000 tonnes of glass annually. This success was made possible using a two-machine sorting process, first using AUTOSORT LASER and then AUTOSORT COLOR.
The first step in the process of removing glass from MSW is pre-treatment. After the MSW infeed material passes through a bag opener, conventionally the fine fraction (0-80 mm) is screened out. This fraction is then split into three categories by a double-deck vibrating screen: fine fractions of 0-8mm diameter, such as organic waste and sand, a middle fraction of 8-60mm and an oversize
fraction of 60-80 mm.
In the second step, the middle fractions, which contain the highest glass content, are subjected to density separation. This removes the lighter fractions and sends the heavier fractions to the AUTOSORT LASER unit where a combination of laser (LAS) and near-infrared (NIR) detection technologies enables the separation of glass from the rest of the materials.
In the third and final step of the process, the innovative AUTOSORT COLOR unit classifies the glass fractions with a high-performance camera and separates any remaining impurities from the higher-quality glass. The result is the recovery of resaleable glass with a consistently high purity of more than 95%.