The Ballistor:
A Game Changer

Image: Raw materials instead of fuel. In the ReWaste F project, funded in part by the Austrian Climate Change and Economic Ministry, the Komptech ballistic separator turned out to be a real game-changer.

Boosting the recycling rates of mixed household and commercial waste is a high priority in the EU. Therefore it is not just a matter of sustainability, but also a legal mandate, to optimize the treatment of mixed wastes for the purpose of reclaiming recyclables. One of these materials that has hitherto garnered little attention is polypropylene (PP). This plastic is used in the auto industry, food packaging, medical technology and many other places, but is very rarely recycled. That is now set to change.

In the ReWaste F research project, with the help of a Komptech ballistic separator it was possible to recover PP with a very high degree of purity. This was used to make a PP granulate, from which new plastic products were manufactured. All of the recycled material, totalling 460 kg, was used to make practical items like buckets and stackable crates. In the next step the processing setup, which worked well at trial scale, will be further tested and expanded to an economically viable scale in order to demonstrate the practical implementation.

Image: The Ballistor enables fraction-specific separation based on ballistic properties.

AS PURE AS POSSIBLE

So how does the Ballistor work? This Komptech machines separates various waste and recyclable mixes. As the name implies, it uses ballistics to separate these streams into a two-dimensional, a three-dimensional and a fine fraction. Up until now, high calorific fractions have mostly been processed into refuse-derived fuels. The degree of purity plays a subordinate role in thermal use – what counts most is the calorific value. Processing recyclables into usable raw materials is a different matter. In plastics, high degree of purity is the critical factor for making a high-quality granulate suitable for use in the circular economy. And here the Ballistor is a real game-changer. During an extensive study that was also part of the ReWaste F project, multiple project partners collaborated to take a close look at the degree of separation provided by this ballistic separator, and optimize it through appropriate adjustments.

FOLLOW-UP AND EVALUATION

The fractions that emerge from the separator vary depending on the machine settings, like the angle of the screen elements and the speed of airflow from the fan. To get the optimum settings for mixed waste, the University of Leoben research team ran a total of 22 trial configurations. All started with pre-shredded commercial waste. To determine the degree of separation, the materials were made traceable using RFID (radio frequency identification), with selected particles being marked so they could later be identified in the respective fractions. After each test run RFID sensors automatically evaluated the material distribution and purity of fractions achieved with the various settings. For every test run, the angle of the screen elements and the airflow speed were modified and the results compared.

IMPRESSIVE RESULTS

Economic viability is determined by a number of factors. In addition to waste composition, these include raw material and energy prices. Government action is required in order to create the right conditions to make recycling competitive. In any case, the Ballistor showed what it can do as regards purity from mixed waste, achieving 94% purity in trials. Material analyses confirm that for plastics, this meets the material requirements for the manufacture of new plastic products. The homogeneous material separated out by the Ballistor is ideal for making recyclate, which can be used as a replacement raw material in the product cycle. This conserves resources, helps protects the environment, and is sustainable.

WHAT IS REWASTE F? 

ReWaste F is a COMET-K project focusing on the recycling and reclamation of waste for future use. The Ministry of Climate Protection and Economy supports the project, as do the Austrian states and several partners.

ReWaste F consists of six individual projects in which the recyclability of various waste materials is analysed. The sorting, prepping and recycling of the waste streams are done by Komptech machines and systems by other partners.