Waste use – a challenge for the 21st century

Waste use – a challenge for the 21st century
Waste is not only a complication, but also possible source of secondary by-products. By minimising waste, we contribute to both a lower ecological burden and the better economy of the company.

Our objective is to reduce waste volume and reuse to the maximum extent those materials that are considered non-recyclable. For example, waste containing PVC cannot usually be combusted ecologically. The only option is a waste site, which however does not provide any material or energy effects but even brings costs to the company – waste disposal charges. So how do we optimise our waste management? We have focused on the waste generated in the production of roof waterproofing insulations, so-called “PES oakum”, and tried to find a method for processing it. And as they say – everything comes to those who search.
This non-standard waste is produced from the trims of membranes and other technological waste. At the current production volume, we produce about 200 tonnes of it annually and this amount will almost double when we launch the new rolling mill. It is waste formed of a composite of fibres connected with PVC particles.
It is unfortunately this inconvenient combination of materials that cannot be reused all at once without modifications – technologies suitable for PVC moulding are not applicable to PES and vice versa. Each of these polymers requires different processing conditions, so the optimum solution for oakum use would be to separate the individual polymers, which is in practice impossible. Another solution is oakum pre-treatment which allows for its use in PVC processing technologies. It is this area that has been precisely dealt with by the EPSILON project.
It all began when Fatra met with representatives of the Faculty of Civil Engineering of VUT Brno and the Faculty of Technology of UTB Zlín in 2014. A team of specialists in the areas of civil engineering and processing of polymeric materials arranged with our management to attempt to find a solution for the utilisation of various technological wastes, including the above-mentioned oakum. Based on this decision, a grant application was made to the EPSILON programme announced by Technological Agency of the Czech Republic (TA CR). (Editorial comment – Ing. Tupý, Ph.D., was at that time a VUT representative, and he was employed by our company in 2015)

The EPSILON project has run virtually since 2015.
The EPSILON project has run virtually since 2015. In addition to VUT and UTB, it was joined by a fifteen-member team of our experts, process engineers and laboratory workers, led by Ing. Tupý and Ing. Novák. In 2010–2017, the researchers managed to analyse in detail the constitution, including the material characteristics, of the PES oakum. The team found out that it is crucial for oakum processing to ensure shorter PES fibres, reduced from about 10 mm to less than 3 mm. In this condition, the oakum can be reprocessed in a mixture with softened PVC without significant deterioration in the end-use properties of the product.
Various technologies were tested with a view to obtaining micro-milled oakum, and the team was ultimately successful. By shortening the fibres, a fine mixture was achieved, but then it was found that it was impossible to process this in the mixing node of the rolling line. Therefore we had to find another way to compact the milled oakum and form granulated material from the dust. The next objective was therefore to design technology that would be able to make these modifications in a single step. The final tests were performed using the company’s BOCO Pardubice machines, the capabilities of which approximated best to our vision. We are currently looking for suppliers for the corresponding production facility: a public tender will be advertised in 2018. Although the installation of a new line will require considerable investment, according to our analysis we anticipate a quick return on investment. The project should be realised at the end of 2019.
The use of granulated oakum as a return material is considered mainly in the production of laminated waterproofing membranes. We anticipate that all waste oakum, i.e. about 200 tonnes per annum, will be being used by 2020, and thanks to the planned production increase of waterproofing membranes, more than 350 tonnes of oakum a year will be being reused from 2025. Another option for using the oakum as a return material is in the production of tiles or foils designed for the construction industry. For example, we are considering this for the production of injection-moulded pads for flat roofs that form part of the FATRAFOL-S system. Other uses include injection-moulded tiles for industrial purposes or hobby floor coverings, which have already been tested by FORTEMIX. We envisage this to become a reality in 2020.
Participation in the EPSILON project represented three years of active work that is still far from being complete. But it was worth it. If we manage to fulfil our ideas, we can reduce the ecological burden of the region considerably, and, in addition, its positive impact on our finances will not be negligible.