PETpla.net Insider 06 / 2016

MATERIAL / RECYCLING 20 PET planet insider Vol. 17 No. 06/16 www.petpla.net Efficient chemicals and technologies for PET recycling Finding the optimal process CHT/Bezema Group has nearly 2,000 staff members employed by 20 companies and was established at Tübingen, Germany more than 60 years ago. The group has focused on spe- cial chemicals. Since 2008, the know-how and years of experience in textile finishing have been successfully transferred to mechanical PET recycling. The recycling business of CHT/ Bezema Group has become an established player worldwide in the interesting PET recycling market in supporting the PET recycling process with sustainable and efficient process aids. Intelligent process aids for quality improvement and process optimisation The consistently high quality of a recycled product as well as optimisa- tion throughout all process stages are crucial pre-requisites for a successful PET recycling company. The require- ments differ from country to country and from recycler to recycler. Finding the optimal process solution is a chal- lenge every day. Bottles from a deposit system Dirty bottles (no deposit system) Cleaning that is visible The cleaning additives of the Tubi- wash range remove adhering soilings and prevent deposits from sticking to machine parts in the aqueous clean- ing stage of PET recycling. In addi- tion, Tubiwash is able to reduce the consumption of energy and caustic soda in the cleaning process. PET-flakes after roasting test (220°C, 30min) cleaned without Tubiwash/with Tubiwash (right) Reduced foam formation leads to better machine operation In the recycling process of PET there is mostly a foam formation which prevents an optimum machine opera- tion. Therefore a defoamer is often indispensable and helps by diffus- ing into the foam lamellae in order to destabilise and finally destroy them. The applied quantity can, however, be reduced to a minimum by using the effective products of the Tubifoam range. They inhibit foam occurring in the various process stages ensuring thus an optimum machine operation. Product solutions for water recycling such as e.g. ultrafiltration also belong to the groups’ portfolio. Perfect separation helps to recycle the different polymers effectively In the PET recycling process the PET needs to be separated from other polymers such as e.g. PP or PE. This procedure is mostly done by means of flotation where air inclusions on the PET flakes may be dramatically impaired this separation. Specialised flotation auxiliaries, namely Tubiwet products, supersede the air adhering to the flakes and facilitate thus a sinking of the PET flakes in the flotation bath. Thus the dif- ferent polymers can be recycled sepa- rately with a high varietal purity. Some of the defoamers of the Tubifoam range are not only used for inhibiting foam but also as flotation auxiliaries. This helps reduce the number of products used in the PET recycling process. Air adhering to the PET-flakes Cleaning and more The consistently high quality of a recycled product as well as optimisa- tion throughout all process stages are crucial pre-requisites for a successful recycling company. Therefore besides a broad product range of intelligent cleaning additives for quality improvement and process optimisation CHT/Bezema offers sev- eral measuring methods for controlling the quality of cleaned PET flakes. It is a valuable part of the service to sup- port the PET recyclers worldwide by well-qualified technical service team. CHT/Bezema focuses on producing sustainable process aids. Products of the CHT/Bezema Group used in the recycling process can be eliminated from the wastewater and are thus envi- ronmentally friendly. www.cht.com RECYCLING S P E C I A L