Material-friendly recycling

Erema Plastic Recycling Systems (www.erema.at) presented its new Intarema? K system for the first time at interpack 2014 in Germany. The new model is the successor of the KAG system designed especially for the recycling of PE edge trim – a fully automatic recycling system which ensures material-friendly processing through a short extruder, i.e. minimal thermomechanical stress and excellent material properties as a result.

The new plant generation Intarema was launched in 2013, with which the T and TE systems (for PE, PE-LD, PP, BOPA, PA/PET, PLA etc. edge trim) and TVEplus (heavily printed materials and strongly contaminated post-consumer waste) have already experienced an enormous boost in efficiency.

The fully automatic Intarema? K recycling system features the new, patented core technology Counter Current, the energy-saving ecoSAVE system including direct drive and, for the first time, a touchscreen, the new Smart Start System for even more user-friendliness through a high degree of automation. Intarema K is designed above all for the processing of edge trim and enables an up to 100% return to the production process.

The company also launched another model, Intarema? 1108 T system, at CHINAPLAS 2014 with efficiency boost and a throughput of e.g. 600 kg/h when processing BOPP. With the patented Counter Current system, the central core technology of the new Intarema plant, Erema is setting another milestone in the plastic recycling systems.

The innovation is in the interface area of the cutter/compactor and extruder. To date the worldwide technical standard has been a system in which the material in the cutter/compactor moved in the direction of the extruder. The difference with the Counter Current system is that the material spout in the cutter/compactor is now reversed and thus moves against the direction of the extruder. The result of this inverse-tangential configuration is increased process stability and, at the same time, considerably higher throughput.

Elimination of unwanted materials

In the field of sorting, washing and recycling of PET, the patented system from AMUT S.p.A. (www.amut.it) has been revolutionary that it guarantees the complete elimination of impurities from recycled PET by using a continuous and carefully controlled process. All this with a water consumption reduced by two-thirds compared to all other cleaning systems. What makes this interesting is that the AMUT plant allows a substantial saving of water: actually it uses only one litre of water per kg of PET (compared to 3 litres used by competitors), and the final product has high purity levels (levels of organic residues are in the order of 20ppm, compared to 100/200 of the other systems on the market).

The Friction Washer has the function of eliminating from the PET flakes (or from the bottles) any type of polluting material: labels, glue, residues of organic substances and surface dirt. The machine is fed directly from an external screw conveyor, which transports the material to be processed and discharges it into the entrance mouth. Inside the Friction Washer, the PET is washed with hot water and chemicals, soda and detergent. The task of the soda is to attack the organic soils (especially glue labels), whilst the detergent prevents glue and pollutant from redepositing on the surface of the flakes.

During the permanence of the product in the drum, the combined action of the friction generated by the rotor, together with the action of hot water and chemicals, enables a perfect washing of the PET flakes. The operation of the machine is automatic and continuous, which means that the same quantity of material enters and comes out after being treated for a certain time.

The residence time of the material being treated is a determining factor for the success of the washing action. Normally this setting is done when the system is started, but if necessary, it can be changed by the operator. The water coming out of the Friction Washer, together with the impurities (traces of paper, glue, etc..) is treated with a special kieselguhr vacuum filter, and is recirculated through a heat exchanger which resets the working temperature parameters.

The system ensures residence time control, as this is a continuous system: entering material pushes the residing material towards the exit so that there is no chaotic movement inside and the residence time is controlled by the ratio volume / flow rate. It also enables friction coefficient control and temperature control as the process requires a well defined temperature, which is automatically maintained by the control system, through hot-water supply and, when necessary, direct steam injection.

The Friction Washer is connected with a flow water recirculation and filtering system. Once the pollutants have been detached by friction, they are continuously collected and discharged by water flow in order to avoid any random deposit.

Another product is the AMUT MINI PRF sorting and pre-washing system which has been developed to improve the quality of recycled PET. It has been a known fact that the quality of bottles has been worsening each day. Some years ago, the contamination of material at the inlet of the washing lines was about 20-25%. Today it is more than 40%. Some of the causes include the growing diffusion of PET as material which is also used for other liquids different from beverages. Also, the new conservation and protection techniques for beverages and food often clash with recycling exigencies. Think about multi-layer barriers of some bottles, caps safety seals or PET-G thermoformed trays to allow the lamination of the covering film. Another cause is reflected in the low efficiency of various selection plants that are not suitable for the new and more challenging stream quality for technical or economic reasons. In addition, the non-convenience for MRF and PRF companies to select and reject good PET only because it is contaminated by sleeve labels or other elements necessary for packaging raises the figure.

The recyclers complaint about the increasing worsening of the quality of material to be treated was the incentive for AMUT Recycling Division to design a “pre-treatment” that completes the wide range of machinery for post-consumer PET valorisation and this new high efficiency upfront system to feed PET bottles wash lines is the result.

The new technology overcomes the lower quality of Comingle Bales and improves both efficiency and yield of the recycling plants. The MINI PRF system includes a pre-selection of the bales, to eliminate all of the pollutant materials in a dry phase and have just the clean bottle stream go through the sorting and a pre-washing equipment, without those foreign materials that create inefficiency, more scraps volume for disposal and higher Imaintenance costs.

The main equipment to perform this task is the AMUT Elliptical Ballistic Separator. This low maintenance machine has the function to mechanically select the bottles stream after the Bale Breakers and eliminate the fines and the 2D pollutants such as carton board, paper and packaging films. De-Labeller / Pre-Wash System will prepare the bottles for the following NIR sorters line. The Pre-Selection and De-Labeler action of the MINI PRF drastically improve the efficiency of the NIRs with better results on the yield of the plant.