The problem of of non-tobacco related materials (NTRM), which is always present in raw tobacco, is more serious than it appears at first glance: one tonne of untreated tobacco can be expected to contain about 100 grams of foreign material and an average of 1,000 non-tobacco particles. Cutting the tobacco increases the number of these particles to around 10,000 per tonne. If one tonne of tobacco is used to make 70,000 packs of cigarettes, one in seven packs will contain a non-tobacco particle unless the manufacturer takes preventive measures. “When you explain it that way, nobody doubts the need for NTRM detection,” explains Frank Schuster, Head of Engineering at Hauni. “The big question is which solution offers the most advantages in the long term.”
Better early than late
There are several issues to consider. Some cigarette manufacturers simply rely on NTRM detection in the maker. But this is far from an optimal solution. Firstly, there is the risk of not detecting NTRM at all. In this case, the first person to notice the quality problem would be the consumer. Secondly, the number of NTRM particles increases dramatically during the cutting process. Moreover, the maker may reject up to ten cigarettes when it detects NTRM and this is extremely wasteful of tobacco, paper and filters. Nor does the exclusive use of metal detectors – which are mainly used to protect equipment and only remove ferro-magnetic objects from the tobacco – eliminate the negative effects of NTRM.
Lower costs, higher efficiency
Even monitoring NTRM with laser sorters – a widely used solution – has its pitfalls. “Not only do laser solutions consume a lot of spare parts, they also require highly qualified operators and maintenance personnel. This creates major difficulties in everyday production. The lasers have to be calibrated and replaced regularly by external specialists,” explains Schuster. “If the manufacturer fails to adhere meticulously to the specified maintenance intervals, there will be a steady drop in sorting performance – which can lead to a total breakdown.”
PURE – the enhanced, camera-based belt sorter developed by the Hauni Group – solves all these problems. Its camera-based technology is more robust and easier to handle than laser systems. It requires few spare parts and, naturally, no replacement of lasers. Handling and maintenance are very easy, and employees can operate the system after just a short introduction.
“As a result, we can reduce maintenance costs by up to two thirds and the system achieves a constant sorting efficiency of more than 85 percent under optimum conditions, with a tobacco loss of less than 0.3 percent,” says Schuster. “In order to achieve this level of performance, our PURE family – developed in collaboration with the Fraunhofer Institute for Optronics, Systems Technologies and Image Exploitation – features the latest image processing technology, state-of-the-art cameras and LED lighting strips. We are proud to present our customers with the world’s most efficient optical sorter.”
