2013-2014 Exhibitions
In time for its 30th anniversary in the industry, Austria-headquartered Erema has also launched a plant system with new core technology at the K 2013 in Düsseldorf, Germany.
Intarema, a name derived from INverse + TAngential + eREMA, is based on the firm’s newly developed and globally patented Counter Current technology. Erema says that their technology fuses excellent productivity, flexibility and ease of operation with considerably lower energy consumption.
The patented Counter Current system, Intarema’s central core technology shows its impact in the border area of the cutter/compactor and tangentially connected extruder. Inside the cutter/compactor the rotation of the rotor disc, which is equipped with tools forms a rotating spout so that the material is circulating the whole time.
In the Counter Current system, the material spout - unlike the previous technical standard - moves against the direction of the extruder. As a result, the relative speed of the material in the intake zone, i.e., when passing from the cutter/compactor to the extruder, increases to such an extent that the extruder screw acts in the same way as a sharp cutting edge which now cuts the plastic. The result of this inverse tangential configuration of the new Intarema plants the extruder handles more material in a shorter time and is much more independent in terms of the pre-compacting level of the material.
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 centrifugal forces arising in the process were used for the feeding of the extruder and the treated, warm material was thus "packed" into the extruder screw. The inverse tangential configuration of the Counter Current system, on the other hand, now ensures that the extruder screw is filled virtually pressure-free with the preheated material.
"The screw basically "takes what it needs", the extruder always has the ideal filling level and is never overfilled, which makes it much better to regulate, " explains Michael Heitzinger, CTO at Erema . He further explains the positive impact, which the new system has on productivity and the quality of the recyclate.
Intarema offers improved material intake over extended temperature range. The system offers sufficiently high flexibility in order to be able to react to faster input changes when recycling to make valuable secondary raw materials. Inside the cutter/compactor the feed material is buffered and preconditioned optimally for the extrusion process. The material is cut, homogenised, warmed, dried and above all compacted to ensure constant extruder feeding. Here it is crucial that the temperature inside the cutter/compactor influences the degree of compacting of the material: the higher the temperature, the higher the degree of plastic material compacting. With the Counter Current system the feeding of the extruder from the cutter/compactor hardly depends on the compacting level of the plastic material, which in turn considerably broadens the range for optimum extruder feeding. This means that the recycling system is not only more flexible in the selection of the operation point, it is also much more reliable in operation.
Results from development trials (in cooperation with customers of many years) with in-house waste from LLDPE blow film production with a thickness of 30 μm document the effect of the Counter Current system on the increased process stability, productivity and flexibility of the new Intarema plant. "Besides extremely easy operation, a stable and sensitive recycling process is essential to be able to ensure recycling rates of 100 % high-quality recyclate in virgin material grade, particularly when processing clean in-house waste from production," says Heitzinger.
With the system used previously the packing and pressure had the risk of sticking, especially in the case of very light materials with low energy content (such as fibres or thin packaging films) or materials with a very low softening point (such as PLA), which could mean reduced material intake. With Counter Current technology, thanks to the improved material intake, capacity is not only increased, it also stays at a constantly high level over a much broader temperature range. The operation range for optimum system capacity has thus been extended considerably. As a result, temperature changes in the cutter/compactor due to fluctuations in feeding have hardly any effect on plant performance and the quality of the recyclate. In addition to this there is also greater flexibility in the selection of the optimum operation point. This is of particular advantage when processing very temperature-sensitive materials.
Intarema exhibits constant output despite input fluctuations. The technology also represents a quantum leap in the field of post-consumer recycling, according to Erema. It stands out here above all through its high degree of flexibility.
Although the input material typically fluctuates highly in terms of moisture, compactness and other parameters, the new technology ensures that the throughput and quality of the recycled pellets produced remain at a constantly high level. The fluctuations in post-consumer recycling result not only from mixed fractions of varying compositions, moisture, viscosity, type and degree of contamination but also especially from differently printed and laminated materials in the packaging sector.
The new system also gives you the highest possible flexibility when processing materials with particularly high input moisture and contamination levels, such as e.g., washed agricultural films, washed post-consumer film flakes (PE-LD, PE-LLD, PE-HD), films with solid content such as paper, wood or metals and also thick-walled regrind materials from waste automobile and electronic goods, PS cups and PE lids.
The recycling of car batteries, for example, is an interesting example of an application. The Intarema T recycling system with single screw extruder (without extruder degassing) and cutter/compactor tools optimised especially for this application offers the perfect technology for the processing of polypropylene (PP) from car batteries which are recovered, washed and broken up into chips.
As these are very thick-walled, moist particles , high residence times in the cutter/compactor are very important so the material is dried efficiently and above all has sufficient time to be warmed thoroughly and homogeneously. With this application-oriented Intarema plant the particles are optimally dried, completely and thoroughly warmed, forwarded to the extruder and the material is then melted carefully in the short extruder screw with minimum shearing strain.
Counter Current technology comes with a further benefit here, which is crucial especially in terms of free-flowing materials such as regrind materials. Whereas the screw was previously susceptible to overfilling, thus resulting in increased shearing forces and signs of wear, the inverse tangential configuration now counteracts this problem. This is made possible by the screw being filled virtually pressure-free and the fact that it takes the exact amount which is required.
Furthermore, the melting process with minimum shear stress increases the cleaning efficiency of the melt filter as the size of organic or mineral solid matter is not reduced. This improves the quality of the recycled pellets, meaning that end products with a considerably higher share of recycled pellets can be produced, such as new battery packs made of up to 100 % recycled pellets.
Last but not the least, Intarema enables enhanced automation with the new, intelligent "Smart Start" concept, through which, many central process steps run completely automatically. Staff at the machine can operate it very easily by pressing just a few buttons - the same worldwide, without having to think about the operating language. This is because the operating concept is based on just a few clear and easy to understand symbols.
The integrated recipe management of Intarema, a particularly practical and time-saving feature, enables plant operators to save all settings and parameters for the optimum result of a special recycling application under one "recipe name" and call it up at any time at the push of a button. A single press on the "Extruder" symbol is enough to start the entire downstream equipment up to the extruder automatically and in the right sequence. If you now press again but this time on the "Cutter/compactor" symbol, the cutter/compactor and automatic feeding begin: the system starts up itself with the recipe set previously, goes into production with the highest degree of safety and works with constantly high quality.
Intarema is equipped with a standby mode, which automatically switches the system to standby if there is no input material and reduces it to a lower operation point - plus the display shows you that material is required. As soon as the system is refilled with input material it starts up automatically again. This function is executed fully automatically by the standby mode - without any operators and without having to press any buttons.
This clearly structured and simple design of the handling enhances the overall accessibility and operability of Intarema systems, which are supplied with the intelligent "Smart Start" as standard, including ultramodern, ergonomic touch display.
An additional innovation featured from the new Erema plant generation is the systematic advancement of ecoSAVE technology (equipped as standard), which enables users to benefit from 10 % less energy consumption, a reduction in CO2 emissions and lower production costs. The overall package of design and process engineering measures includes the highly efficient direct drive of the Intarema extruder screw with an up to 3 % higher degree of extruder efficiency and a practical energy display, which gives a constant overview of energy consumption. Specific measures can also be taken to optimise consumption.
The Intarema systems are available for capacities ranging from 50 to 3,000 kg/h.
(PRA)
